diff --git a/asn1.js b/asn1.js
index 7855118..d157950 100644
--- a/asn1.js
+++ b/asn1.js
@@ -24,7 +24,26 @@ const
     oids = require('./oids'),
     ellipsis = '\u2026',
     reTimeS =     /^(\d\d)(0[1-9]|1[0-2])(0[1-9]|[12]\d|3[01])([01]\d|2[0-3])(?:([0-5]\d)(?:([0-5]\d)(?:[.,](\d{1,3}))?)?)?(Z|(-(?:0\d|1[0-2])|[+](?:0\d|1[0-4]))([0-5]\d)?)?$/,
-    reTimeL = /^(\d\d\d\d)(0[1-9]|1[0-2])(0[1-9]|[12]\d|3[01])([01]\d|2[0-3])(?:([0-5]\d)(?:([0-5]\d)(?:[.,](\d{1,3}))?)?)?(Z|(-(?:0\d|1[0-2])|[+](?:0\d|1[0-4]))([0-5]\d)?)?$/;
+    reTimeL = /^(\d\d\d\d)(0[1-9]|1[0-2])(0[1-9]|[12]\d|3[01])([01]\d|2[0-3])(?:([0-5]\d)(?:([0-5]\d)(?:[.,](\d{1,3}))?)?)?(Z|(-(?:0\d|1[0-2])|[+](?:0\d|1[0-4]))([0-5]\d)?)?$/,
+    b64Safe = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_',
+    tableT61 = [
+        ['', ''],
+        ['AEIOUaeiou', 'ÀÈÌÒÙàèìòù'], // Grave
+        ['ACEILNORSUYZacegilnorsuyz', 'ÁĆÉÍĹŃÓŔŚÚÝŹáćéģíĺńóŕśúýź'], // Acute
+        ['ACEGHIJOSUWYaceghijosuwy', 'ÂĈÊĜĤÎĴÔŜÛŴŶâĉêĝĥîĵôŝûŵŷ'], // Circumflex
+        ['AINOUainou', 'ÃĨÑÕŨãĩñõũ'], // Tilde
+        ['AEIOUaeiou', 'ĀĒĪŌŪāēīōū'], // Macron
+        ['AGUagu', 'ĂĞŬăğŭ'], // Breve
+        ['CEGIZcegz', 'ĊĖĠİŻċėġż'], // Dot
+        ['AEIOUYaeiouy', 'ÄËÏÖÜŸäëïöüÿ'], // Umlaut or diæresis
+        ['', ''],
+        ['AUau', 'ÅŮåů'], // Ring
+        ['CGKLNRSTcklnrst', 'ÇĢĶĻŅŖŞŢçķļņŗşţ'], // Cedilla
+        ['', ''],
+        ['OUou', 'ŐŰőű'], // Double Acute
+        ['AEIUaeiu', 'ĄĘĮŲąęįų'], // Ogonek
+        ['CDELNRSTZcdelnrstz', 'ČĎĚĽŇŘŠŤŽčďěľňřšťž'] // Caron
+    ];
 
 function stringCut(str, len) {
     if (str.length > len)
@@ -32,226 +51,6 @@ function stringCut(str, len) {
     return str;
 }
 
-function Stream(enc, pos) {
-    if (enc instanceof Stream) {
-        this.enc = enc.enc;
-        this.pos = enc.pos;
-    } else {
-        // enc should be an array or a binary string
-        this.enc = enc;
-        this.pos = pos;
-    }
-}
-Stream.prototype.get = function (pos) {
-    if (pos === undefined)
-        pos = this.pos++;
-    if (pos >= this.enc.length)
-        throw 'Requesting byte offset ' + pos + ' on a stream of length ' + this.enc.length;
-    return (typeof this.enc == 'string') ? this.enc.charCodeAt(pos) : this.enc[pos];
-};
-Stream.prototype.hexDigits = '0123456789ABCDEF';
-Stream.prototype.hexByte = function (b) {
-    return this.hexDigits.charAt((b >> 4) & 0xF) + this.hexDigits.charAt(b & 0xF);
-};
-Stream.prototype.hexDump = function (start, end, raw) {
-    let s = '';
-    for (let i = start; i < end; ++i) {
-        s += this.hexByte(this.get(i));
-        if (raw !== true)
-            switch (i & 0xF) {
-            case 0x7: s += '  '; break;
-            case 0xF: s += '\n'; break;
-            default:  s += ' ';
-            }
-    }
-    return s;
-};
-const b64Safe = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_';
-Stream.prototype.b64Dump = function (start, end) {
-    let extra = (end - start) % 3,
-        s = '',
-        i, c;
-    for (i = start; i + 2 < end; i += 3) {
-        c = this.get(i) << 16 | this.get(i + 1) << 8 | this.get(i + 2);
-        s += b64Safe.charAt(c >> 18 & 0x3F);
-        s += b64Safe.charAt(c >> 12 & 0x3F);
-        s += b64Safe.charAt(c >>  6 & 0x3F);
-        s += b64Safe.charAt(c       & 0x3F);
-    }
-    if (extra > 0) {
-        c = this.get(i) << 16;
-        if (extra > 1) c |= this.get(i + 1) << 8;
-        s += b64Safe.charAt(c >> 18 & 0x3F);
-        s += b64Safe.charAt(c >> 12 & 0x3F);
-        if (extra == 2) s += b64Safe.charAt(c >> 6 & 0x3F);
-    }
-    return s;
-};
-Stream.prototype.isASCII = function (start, end) {
-    for (let i = start; i < end; ++i) {
-        let c = this.get(i);
-        if (c < 32 || c > 176)
-            return false;
-    }
-    return true;
-};
-Stream.prototype.parseStringISO = function (start, end, maxLength) {
-    let s = '';
-    for (let i = start; i < end; ++i)
-        s += String.fromCharCode(this.get(i));
-    return { size: s.length, str: stringCut(s, maxLength) };
-};
-const tableT61 = [
-    ['', ''],
-    ['AEIOUaeiou', 'ÀÈÌÒÙàèìòù'], // Grave
-    ['ACEILNORSUYZacegilnorsuyz', 'ÁĆÉÍĹŃÓŔŚÚÝŹáćéģíĺńóŕśúýź'], // Acute
-    ['ACEGHIJOSUWYaceghijosuwy', 'ÂĈÊĜĤÎĴÔŜÛŴŶâĉêĝĥîĵôŝûŵŷ'], // Circumflex
-    ['AINOUainou', 'ÃĨÑÕŨãĩñõũ'], // Tilde
-    ['AEIOUaeiou', 'ĀĒĪŌŪāēīōū'], // Macron
-    ['AGUagu', 'ĂĞŬăğŭ'], // Breve
-    ['CEGIZcegz', 'ĊĖĠİŻċėġż'], // Dot
-    ['AEIOUYaeiouy', 'ÄËÏÖÜŸäëïöüÿ'], // Umlaut or diæresis
-    ['', ''],
-    ['AUau', 'ÅŮåů'], // Ring
-    ['CGKLNRSTcklnrst', 'ÇĢĶĻŅŖŞŢçķļņŗşţ'], // Cedilla
-    ['', ''],
-    ['OUou', 'ŐŰőű'], // Double Acute
-    ['AEIUaeiu', 'ĄĘĮŲąęįų'], // Ogonek
-    ['CDELNRSTZcdelnrstz', 'ČĎĚĽŇŘŠŤŽčďěľňřšťž'] // Caron
-];
-Stream.prototype.parseStringT61 = function (start, end, maxLength) {
-    // warning: this code is not very well tested so far
-    function merge(c, d) {
-        let t = tableT61[c - 0xC0];
-        let i = t[0].indexOf(String.fromCharCode(d));
-        return (i < 0) ? '\0' : t[1].charAt(i);
-    }
-    let s = '', c;
-    for (let i = start; i < end; ++i) {
-        c = this.get(i);
-        if (c >= 0xA4 && c <= 0xBF)
-            s += '$¥#§¤\0\0«\0\0\0\0°±²³×µ¶·÷\0\0»¼½¾¿'.charAt(c - 0xA4);
-        else if (c >= 0xE0 && c <= 0xFF)
-            s += 'ΩÆЪĦ\0IJĿŁØŒºÞŦŊʼnĸæđðħıijŀłøœßþŧŋ\0'.charAt(c - 0xE0);
-        else if (c >= 0xC0 && c <= 0xCF)
-            s += merge(c, this.get(++i));
-        else // using ISO 8859-1 for characters undefined (or equal) in T.61
-            s += String.fromCharCode(c);
-    }
-    return { size: s.length, str: stringCut(s, maxLength) };
-};
-Stream.prototype.parseStringUTF = function (start, end, maxLength) {
-    function ex(c) { // must be 10xxxxxx
-        if ((c < 0x80) || (c >= 0xC0))
-            throw new Error('Invalid UTF-8 continuation byte: ' + c);
-        return (c & 0x3F);
-    }
-    function surrogate(cp) {
-        if (cp < 0x10000)
-            throw new Error('UTF-8 overlong encoding, codepoint encoded in 4 bytes: ' + cp);
-        // we could use String.fromCodePoint(cp) but let's be nice to older browsers and use surrogate pairs
-        cp -= 0x10000;
-        return String.fromCharCode((cp >> 10) + 0xD800, (cp & 0x3FF) + 0xDC00);
-    }
-    let s = '';
-    for (let i = start; i < end; ) {
-        let c = this.get(i++);
-        if (c < 0x80) // 0xxxxxxx (7 bit)
-            s += String.fromCharCode(c);
-        else if (c < 0xC0)
-            throw new Error('Invalid UTF-8 starting byte: ' + c);
-        else if (c < 0xE0) // 110xxxxx 10xxxxxx (11 bit)
-            s += String.fromCharCode(((c & 0x1F) << 6) | ex(this.get(i++)));
-        else if (c < 0xF0) // 1110xxxx 10xxxxxx 10xxxxxx (16 bit)
-            s += String.fromCharCode(((c & 0x0F) << 12) | (ex(this.get(i++)) << 6) | ex(this.get(i++)));
-        else if (c < 0xF8) // 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx (21 bit)
-            s += surrogate(((c & 0x07) << 18) | (ex(this.get(i++)) << 12) | (ex(this.get(i++)) << 6) | ex(this.get(i++)));
-        else
-            throw new Error('Invalid UTF-8 starting byte (since 2003 it is restricted to 4 bytes): ' + c);
-    }
-    return { size: s.length, str: stringCut(s, maxLength) };
-};
-Stream.prototype.parseStringBMP = function (start, end, maxLength) {
-    let s = '', hi, lo;
-    for (let i = start; i < end; ) {
-        hi = this.get(i++);
-        lo = this.get(i++);
-        s += String.fromCharCode((hi << 8) | lo);
-    }
-    return { size: s.length, str: stringCut(s, maxLength) };
-};
-Stream.prototype.parseTime = function (start, end, shortYear) {
-    let s = this.parseStringISO(start, end).str,
-        m = (shortYear ? reTimeS : reTimeL).exec(s);
-    if (!m)
-        return 'Unrecognized time: ' + s;
-    if (shortYear) {
-        // to avoid querying the timer, use the fixed range [1970, 2069]
-        // it will conform with ITU X.400 [-10, +40] sliding window until 2030
-        m[1] = +m[1];
-        m[1] += (m[1] < 70) ? 2000 : 1900;
-    }
-    s = m[1] + '-' + m[2] + '-' + m[3] + ' ' + m[4];
-    if (m[5]) {
-        s += ':' + m[5];
-        if (m[6]) {
-            s += ':' + m[6];
-            if (m[7])
-                s += '.' + m[7];
-        }
-    }
-    if (m[8]) {
-        s += ' UTC';
-        if (m[9])
-            s += m[9] + ':' + (m[10] || '00');
-    }
-    return s;
-};
-Stream.prototype.parseInteger = function (start, end) {
-    let v = this.get(start),
-        neg = (v > 127),
-        pad = neg ? 255 : 0,
-        len,
-        s = '';
-    // skip unuseful bits (not allowed in DER)
-    while (v == pad && ++start < end)
-        v = this.get(start);
-    len = end - start;
-    if (len === 0)
-        return neg ? '-1' : '0';
-    // show bit length of huge integers
-    if (len > 4) {
-        s = v;
-        len <<= 3;
-        while (((s ^ pad) & 0x80) == 0) {
-            s <<= 1;
-            --len;
-        }
-        s = '(' + len + ' bit)\n';
-    }
-    // decode the integer
-    if (neg) v = v - 256;
-    let n = new Int10(v);
-    for (let i = start + 1; i < end; ++i)
-        n.mulAdd(256, this.get(i));
-    return s + n.toString();
-};
-Stream.prototype.parseBitString = function (start, end, maxLength) {
-    let unusedBits = this.get(start);
-    if (unusedBits > 7)
-        throw 'Invalid BitString with unusedBits=' + unusedBits;
-    let lenBit = ((end - start - 1) << 3) - unusedBits,
-        s = '';
-    for (let i = start + 1; i < end; ++i) {
-        let b = this.get(i),
-            skip = (i == end - 1) ? unusedBits : 0;
-        for (let j = 7; j >= skip; --j)
-            s += (b >> j) & 1 ? '1' : '0';
-        if (s.length > maxLength)
-            s = stringCut(s, maxLength);
-    }
-    return { size: lenBit, str: s };
-};
 function checkPrintable(s) {
     let i, v;
     for (i = 0; i < s.length; ++i) {
@@ -260,118 +59,275 @@ function checkPrintable(s) {
             throw new Error('Unprintable character at index ' + i + ' (code ' + s.str.charCodeAt(i) + ')');
     }
 }
-Stream.prototype.parseOctetString = function (start, end, maxLength) {
-    let len = end - start,
-        s;
-    try {
-        s = this.parseStringUTF(start, end, maxLength);
-        checkPrintable(s.str);
-        return { size: end - start, str: s.str };
-    } catch (e) {
-        // ignore
+
+class Stream {
+
+    constructor(enc, pos) {
+        if (enc instanceof Stream) {
+            this.enc = enc.enc;
+            this.pos = enc.pos;
+        } else {
+            // enc should be an array or a binary string
+            this.enc = enc;
+            this.pos = pos;
+        }
     }
-    maxLength /= 2; // we work in bytes
-    if (len > maxLength)
-        end = start + maxLength;
-    s = '';
-    for (let i = start; i < end; ++i)
-        s += this.hexByte(this.get(i));
-    if (len > maxLength)
-        s += ellipsis;
-    return { size: len, str: s };
-};
-Stream.prototype.parseOID = function (start, end, maxLength, isRelative) {
-    let s = '',
-        n = new Int10(),
-        bits = 0;
-    for (let i = start; i < end; ++i) {
-        let v = this.get(i);
-        n.mulAdd(128, v & 0x7F);
-        bits += 7;
-        if (!(v & 0x80)) { // finished
-            if (s === '') {
-                n = n.simplify();
-                if (isRelative) {
-                    s = (n instanceof Int10) ? n.toString() : '' + n;
-                } else if (n instanceof Int10) {
-                    n.sub(80);
-                    s = '2.' + n.toString();
-                } else {
-                    let m = n < 80 ? n < 40 ? 0 : 1 : 2;
-                    s = m + '.' + (n - m * 40);
+    get(pos) {
+        if (pos === undefined)
+            pos = this.pos++;
+        if (pos >= this.enc.length)
+            throw 'Requesting byte offset ' + pos + ' on a stream of length ' + this.enc.length;
+        return (typeof this.enc == 'string') ? this.enc.charCodeAt(pos) : this.enc[pos];
+    };
+    hexDigits = '0123456789ABCDEF';
+    hexByte(b) {
+        return this.hexDigits.charAt((b >> 4) & 0xF) + this.hexDigits.charAt(b & 0xF);
+    };
+    hexDump(start, end, raw) {
+        let s = '';
+        for (let i = start; i < end; ++i) {
+            s += this.hexByte(this.get(i));
+            if (raw !== true)
+                switch (i & 0xF) {
+                case 0x7: s += '  '; break;
+                case 0xF: s += '\n'; break;
+                default:  s += ' ';
                 }
-            } else
-                s += '.' + n.toString();
+        }
+        return s;
+    };
+    b64Dump(start, end) {
+        let extra = (end - start) % 3,
+            s = '',
+            i, c;
+        for (i = start; i + 2 < end; i += 3) {
+            c = this.get(i) << 16 | this.get(i + 1) << 8 | this.get(i + 2);
+            s += b64Safe.charAt(c >> 18 & 0x3F);
+            s += b64Safe.charAt(c >> 12 & 0x3F);
+            s += b64Safe.charAt(c >>  6 & 0x3F);
+            s += b64Safe.charAt(c       & 0x3F);
+        }
+        if (extra > 0) {
+            c = this.get(i) << 16;
+            if (extra > 1) c |= this.get(i + 1) << 8;
+            s += b64Safe.charAt(c >> 18 & 0x3F);
+            s += b64Safe.charAt(c >> 12 & 0x3F);
+            if (extra == 2) s += b64Safe.charAt(c >> 6 & 0x3F);
+        }
+        return s;
+    };
+    isASCII(start, end) {
+        for (let i = start; i < end; ++i) {
+            let c = this.get(i);
+            if (c < 32 || c > 176)
+                return false;
+        }
+        return true;
+    };
+    parseStringISO(start, end, maxLength) {
+        let s = '';
+        for (let i = start; i < end; ++i)
+            s += String.fromCharCode(this.get(i));
+        return { size: s.length, str: stringCut(s, maxLength) };
+    };
+    parseStringT61(start, end, maxLength) {
+        // warning: this code is not very well tested so far
+        function merge(c, d) {
+            let t = tableT61[c - 0xC0];
+            let i = t[0].indexOf(String.fromCharCode(d));
+            return (i < 0) ? '\0' : t[1].charAt(i);
+        }
+        let s = '', c;
+        for (let i = start; i < end; ++i) {
+            c = this.get(i);
+            if (c >= 0xA4 && c <= 0xBF)
+                s += '$¥#§¤\0\0«\0\0\0\0°±²³×µ¶·÷\0\0»¼½¾¿'.charAt(c - 0xA4);
+            else if (c >= 0xE0 && c <= 0xFF)
+                s += 'ΩÆЪĦ\0IJĿŁØŒºÞŦŊʼnĸæđðħıijŀłøœßþŧŋ\0'.charAt(c - 0xE0);
+            else if (c >= 0xC0 && c <= 0xCF)
+                s += merge(c, this.get(++i));
+            else // using ISO 8859-1 for characters undefined (or equal) in T.61
+                s += String.fromCharCode(c);
+        }
+        return { size: s.length, str: stringCut(s, maxLength) };
+    };
+    parseStringUTF(start, end, maxLength) {
+        function ex(c) { // must be 10xxxxxx
+            if ((c < 0x80) || (c >= 0xC0))
+                throw new Error('Invalid UTF-8 continuation byte: ' + c);
+            return (c & 0x3F);
+        }
+        function surrogate(cp) {
+            if (cp < 0x10000)
+                throw new Error('UTF-8 overlong encoding, codepoint encoded in 4 bytes: ' + cp);
+            // we could use String.fromCodePoint(cp) but let's be nice to older browsers and use surrogate pairs
+            cp -= 0x10000;
+            return String.fromCharCode((cp >> 10) + 0xD800, (cp & 0x3FF) + 0xDC00);
+        }
+        let s = '';
+        for (let i = start; i < end; ) {
+            let c = this.get(i++);
+            if (c < 0x80) // 0xxxxxxx (7 bit)
+                s += String.fromCharCode(c);
+            else if (c < 0xC0)
+                throw new Error('Invalid UTF-8 starting byte: ' + c);
+            else if (c < 0xE0) // 110xxxxx 10xxxxxx (11 bit)
+                s += String.fromCharCode(((c & 0x1F) << 6) | ex(this.get(i++)));
+            else if (c < 0xF0) // 1110xxxx 10xxxxxx 10xxxxxx (16 bit)
+                s += String.fromCharCode(((c & 0x0F) << 12) | (ex(this.get(i++)) << 6) | ex(this.get(i++)));
+            else if (c < 0xF8) // 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx (21 bit)
+                s += surrogate(((c & 0x07) << 18) | (ex(this.get(i++)) << 12) | (ex(this.get(i++)) << 6) | ex(this.get(i++)));
+            else
+                throw new Error('Invalid UTF-8 starting byte (since 2003 it is restricted to 4 bytes): ' + c);
+        }
+        return { size: s.length, str: stringCut(s, maxLength) };
+    };
+    parseStringBMP(start, end, maxLength) {
+        let s = '', hi, lo;
+        for (let i = start; i < end; ) {
+            hi = this.get(i++);
+            lo = this.get(i++);
+            s += String.fromCharCode((hi << 8) | lo);
+        }
+        return { size: s.length, str: stringCut(s, maxLength) };
+    };
+    parseTime(start, end, shortYear) {
+        let s = this.parseStringISO(start, end).str,
+            m = (shortYear ? reTimeS : reTimeL).exec(s);
+        if (!m)
+            return 'Unrecognized time: ' + s;
+        if (shortYear) {
+            // to avoid querying the timer, use the fixed range [1970, 2069]
+            // it will conform with ITU X.400 [-10, +40] sliding window until 2030
+            m[1] = +m[1];
+            m[1] += (m[1] < 70) ? 2000 : 1900;
+        }
+        s = m[1] + '-' + m[2] + '-' + m[3] + ' ' + m[4];
+        if (m[5]) {
+            s += ':' + m[5];
+            if (m[6]) {
+                s += ':' + m[6];
+                if (m[7])
+                    s += '.' + m[7];
+            }
+        }
+        if (m[8]) {
+            s += ' UTC';
+            if (m[9])
+                s += m[9] + ':' + (m[10] || '00');
+        }
+        return s;
+    };
+    parseInteger(start, end) {
+        let v = this.get(start),
+            neg = (v > 127),
+            pad = neg ? 255 : 0,
+            len,
+            s = '';
+        // skip unuseful bits (not allowed in DER)
+        while (v == pad && ++start < end)
+            v = this.get(start);
+        len = end - start;
+        if (len === 0)
+            return neg ? '-1' : '0';
+        // show bit length of huge integers
+        if (len > 4) {
+            s = v;
+            len <<= 3;
+            while (((s ^ pad) & 0x80) == 0) {
+                s <<= 1;
+                --len;
+            }
+            s = '(' + len + ' bit)\n';
+        }
+        // decode the integer
+        if (neg) v = v - 256;
+        let n = new Int10(v);
+        for (let i = start + 1; i < end; ++i)
+            n.mulAdd(256, this.get(i));
+        return s + n.toString();
+    };
+    parseBitString(start, end, maxLength) {
+        let unusedBits = this.get(start);
+        if (unusedBits > 7)
+            throw 'Invalid BitString with unusedBits=' + unusedBits;
+        let lenBit = ((end - start - 1) << 3) - unusedBits,
+            s = '';
+        for (let i = start + 1; i < end; ++i) {
+            let b = this.get(i),
+                skip = (i == end - 1) ? unusedBits : 0;
+            for (let j = 7; j >= skip; --j)
+                s += (b >> j) & 1 ? '1' : '0';
             if (s.length > maxLength)
-                return stringCut(s, maxLength);
-            n = new Int10();
+                s = stringCut(s, maxLength);
+        }
+        return { size: lenBit, str: s };
+    };
+    parseOctetString(start, end, maxLength) {
+        let len = end - start,
+            s;
+        try {
+            s = this.parseStringUTF(start, end, maxLength);
+            checkPrintable(s.str);
+            return { size: end - start, str: s.str };
+        } catch (e) {
+            // ignore
+        }
+        maxLength /= 2; // we work in bytes
+        if (len > maxLength)
+            end = start + maxLength;
+        s = '';
+        for (let i = start; i < end; ++i)
+            s += this.hexByte(this.get(i));
+        if (len > maxLength)
+            s += ellipsis;
+        return { size: len, str: s };
+    };
+    parseOID(start, end, maxLength, isRelative) {
+        let s = '',
+            n = new Int10(),
             bits = 0;
+        for (let i = start; i < end; ++i) {
+            let v = this.get(i);
+            n.mulAdd(128, v & 0x7F);
+            bits += 7;
+            if (!(v & 0x80)) { // finished
+                if (s === '') {
+                    n = n.simplify();
+                    if (isRelative) {
+                        s = (n instanceof Int10) ? n.toString() : '' + n;
+                    } else if (n instanceof Int10) {
+                        n.sub(80);
+                        s = '2.' + n.toString();
+                    } else {
+                        let m = n < 80 ? n < 40 ? 0 : 1 : 2;
+                        s = m + '.' + (n - m * 40);
+                    }
+                } else
+                    s += '.' + n.toString();
+                if (s.length > maxLength)
+                    return stringCut(s, maxLength);
+                n = new Int10();
+                bits = 0;
+            }
         }
-    }
-    if (bits > 0)
-        s += '.incomplete';
-    if (typeof oids === 'object' && !isRelative) {
-        let oid = oids[s];
-        if (oid) {
-            if (oid.d) s += '\n' + oid.d;
-            if (oid.c) s += '\n' + oid.c;
-            if (oid.w) s += '\n(warning!)';
+        if (bits > 0)
+            s += '.incomplete';
+        if (typeof oids === 'object' && !isRelative) {
+            let oid = oids[s];
+            if (oid) {
+                if (oid.d) s += '\n' + oid.d;
+                if (oid.c) s += '\n' + oid.c;
+                if (oid.w) s += '\n(warning!)';
+            }
         }
-    }
-    return s;
-};
-Stream.prototype.parseRelativeOID = function (start, end, maxLength) {
-    return this.parseOID(start, end, maxLength, true);
-};
-
-function ASN1(stream, header, length, tag, tagLen, sub) {
-    if (!(tag instanceof ASN1Tag)) throw 'Invalid tag value.';
-    this.stream = stream;
-    this.header = header;
-    this.length = length;
-    this.tag = tag;
-    this.tagLen = tagLen;
-    this.sub = sub;
+        return s;
+    };
+    parseRelativeOID(start, end, maxLength) {
+        return this.parseOID(start, end, maxLength, true);
+    };
 }
-ASN1.prototype.typeName = function () {
-    switch (this.tag.tagClass) {
-    case 0: // universal
-        switch (this.tag.tagNumber) {
-        case 0x00: return 'EOC';
-        case 0x01: return 'BOOLEAN';
-        case 0x02: return 'INTEGER';
-        case 0x03: return 'BIT_STRING';
-        case 0x04: return 'OCTET_STRING';
-        case 0x05: return 'NULL';
-        case 0x06: return 'OBJECT_IDENTIFIER';
-        case 0x07: return 'ObjectDescriptor';
-        case 0x08: return 'EXTERNAL';
-        case 0x09: return 'REAL';
-        case 0x0A: return 'ENUMERATED';
-        case 0x0B: return 'EMBEDDED_PDV';
-        case 0x0C: return 'UTF8String';
-        case 0x0D: return 'RELATIVE_OID';
-        case 0x10: return 'SEQUENCE';
-        case 0x11: return 'SET';
-        case 0x12: return 'NumericString';
-        case 0x13: return 'PrintableString'; // ASCII subset
-        case 0x14: return 'TeletexString'; // aka T61String
-        case 0x15: return 'VideotexString';
-        case 0x16: return 'IA5String'; // ASCII
-        case 0x17: return 'UTCTime';
-        case 0x18: return 'GeneralizedTime';
-        case 0x19: return 'GraphicString';
-        case 0x1A: return 'VisibleString'; // ASCII subset
-        case 0x1B: return 'GeneralString';
-        case 0x1C: return 'UniversalString';
-        case 0x1E: return 'BMPString';
-        }
-        return 'Universal_' + this.tag.tagNumber.toString();
-    case 1: return 'Application_' + this.tag.tagNumber.toString();
-    case 2: return '[' + this.tag.tagNumber.toString() + ']'; // Context
-    case 3: return 'Private_' + this.tag.tagNumber.toString();
-    }
-};
+
 function recurse(el, parser, maxLength) {
     let avoidRecurse = true;
     if (el.tag.tagConstructed && el.sub) {
@@ -391,210 +347,265 @@ function recurse(el, parser, maxLength) {
     });
     return d;
 }
-/** A string preview of the content (intended for humans). */
-ASN1.prototype.content = function (maxLength) {
-    if (this.tag === undefined)
-        return null;
-    if (maxLength === undefined)
-        maxLength = Infinity;
-    let content = this.posContent(),
-        len = Math.abs(this.length);
-    if (!this.tag.isUniversal()) {
-        if (this.sub !== null)
-            return '(' + this.sub.length + ' elem)';
-        let d1 = this.stream.parseOctetString(content, content + len, maxLength);
-        return '(' + d1.size + ' byte)\n' + d1.str;
-    }
-    switch (this.tag.tagNumber) {
-    case 0x01: // BOOLEAN
-        return (this.stream.get(content) === 0) ? 'false' : 'true';
-    case 0x02: // INTEGER
-        return this.stream.parseInteger(content, content + len);
-    case 0x03: { // BIT_STRING
-        let d = recurse(this, 'parseBitString', maxLength);
-        return '(' + d.size + ' bit)\n' + d.str;
-    }
-    case 0x04: { // OCTET_STRING
-        let d = recurse(this, 'parseOctetString', maxLength);
-        return '(' + d.size + ' byte)\n' + d.str;
-    }
-    //case 0x05: // NULL
-    case 0x06: // OBJECT_IDENTIFIER
-        return this.stream.parseOID(content, content + len, maxLength);
-    //case 0x07: // ObjectDescriptor
-    //case 0x08: // EXTERNAL
-    //case 0x09: // REAL
-    case 0x0A: // ENUMERATED
-        return this.stream.parseInteger(content, content + len);
-    //case 0x0B: // EMBEDDED_PDV
-    case 0x0D: // RELATIVE-OID
-        return this.stream.parseRelativeOID(content, content + len, maxLength);
-    case 0x10: // SEQUENCE
-    case 0x11: // SET
-        if (this.sub !== null)
-            return '(' + this.sub.length + ' elem)';
-        else
-            return '(no elem)';
-    case 0x0C: // UTF8String
-        return recurse(this, 'parseStringUTF', maxLength).str;
-    case 0x14: // TeletexString
-        return recurse(this, 'parseStringT61', maxLength).str;
-    case 0x12: // NumericString
-    case 0x13: // PrintableString
-    case 0x15: // VideotexString
-    case 0x16: // IA5String
-    case 0x1A: // VisibleString
-    case 0x1B: // GeneralString
-    //case 0x19: // GraphicString
-    //case 0x1C: // UniversalString
-        return recurse(this, 'parseStringISO', maxLength).str;
-    case 0x1E: // BMPString
-        return recurse(this, 'parseStringBMP', maxLength).str;
-    case 0x17: // UTCTime
-    case 0x18: // GeneralizedTime
-        return this.stream.parseTime(content, content + len, (this.tag.tagNumber == 0x17));
-    }
-    return null;
-};
-ASN1.prototype.toString = function () {
-    return this.typeName() + '@' + this.stream.pos + '[header:' + this.header + ',length:' + this.length + ',sub:' + ((this.sub === null) ? 'null' : this.sub.length) + ']';
-};
-ASN1.prototype.toPrettyString = function (indent) {
-    if (indent === undefined) indent = '';
-    let s = indent + this.typeName() + ' @' + this.stream.pos;
-    if (this.length >= 0)
-        s += '+';
-    s += this.length;
-    if (this.tag.tagConstructed)
-        s += ' (constructed)';
-    else if ((this.tag.isUniversal() && ((this.tag.tagNumber == 0x03) || (this.tag.tagNumber == 0x04))) && (this.sub !== null))
-        s += ' (encapsulates)';
-    let content = this.content();
-    if (content)
-        s += ': ' + content.replace(/\n/g, '|');
-    s += '\n';
-    if (this.sub !== null) {
-        indent += '  ';
-        for (let i = 0, max = this.sub.length; i < max; ++i)
-            s += this.sub[i].toPrettyString(indent);
-    }
-    return s;
-};
-ASN1.prototype.posStart = function () {
-    return this.stream.pos;
-};
-ASN1.prototype.posContent = function () {
-    return this.stream.pos + this.header;
-};
-ASN1.prototype.posEnd = function () {
-    return this.stream.pos + this.header + Math.abs(this.length);
-};
-/** Position of the length. */
-ASN1.prototype.posLen = function() {
-    return this.stream.pos + this.tagLen;
-};
-ASN1.prototype.toHexString = function () {
-    return this.stream.hexDump(this.posStart(), this.posEnd(), true);
-};
-ASN1.prototype.toB64String = function () {
-    return this.stream.b64Dump(this.posStart(), this.posEnd());
-};
-ASN1.decodeLength = function (stream) {
-    let buf = stream.get(),
-        len = buf & 0x7F;
-    if (len == buf) // first bit was 0, short form
-        return len;
-    if (len === 0) // long form with length 0 is a special case
-        return null; // undefined length
-    if (len > 6) // no reason to use Int10, as it would be a huge buffer anyways
-        throw 'Length over 48 bits not supported at position ' + (stream.pos - 1);
-    buf = 0;
-    for (let i = 0; i < len; ++i)
-        buf = (buf * 256) + stream.get();
-    return buf;
-};
-function ASN1Tag(stream) {
-    let buf = stream.get();
-    this.tagClass = buf >> 6;
-    this.tagConstructed = ((buf & 0x20) !== 0);
-    this.tagNumber = buf & 0x1F;
-    if (this.tagNumber == 0x1F) { // long tag
-        let n = new Int10();
-        do {
-            buf = stream.get();
-            n.mulAdd(128, buf & 0x7F);
-        } while (buf & 0x80);
-        this.tagNumber = n.simplify();
+
+class ASN1 {
+    constructor(stream, header, length, tag, tagLen, sub) {
+        if (!(tag instanceof ASN1Tag)) throw 'Invalid tag value.';
+        this.stream = stream;
+        this.header = header;
+        this.length = length;
+        this.tag = tag;
+        this.tagLen = tagLen;
+        this.sub = sub;
     }
-}
-ASN1Tag.prototype.isUniversal = function () {
-    return this.tagClass === 0x00;
-};
-ASN1Tag.prototype.isEOC = function () {
-    return this.tagClass === 0x00 && this.tagNumber === 0x00;
-};
-ASN1.decode = function (stream, offset) {
-    if (!(stream instanceof Stream))
-        stream = new Stream(stream, offset || 0);
-    let streamStart = new Stream(stream),
-        tag = new ASN1Tag(stream),
-        tagLen = stream.pos - streamStart.pos,
-        len = ASN1.decodeLength(stream),
-        start = stream.pos,
-        header = start - streamStart.pos,
-        sub = null,
-        getSub = function () {
-            sub = [];
-            if (len !== null) {
-                // definite length
-                let end = start + len;
-                if (end > stream.enc.length)
-                    throw 'Container at offset ' + start +  ' has a length of ' + len + ', which is past the end of the stream';
-                while (stream.pos < end)
-                    sub[sub.length] = ASN1.decode(stream);
-                if (stream.pos != end)
-                    throw 'Content size is not correct for container at offset ' + start;
-            } else {
-                // undefined length
-                try {
-                    for (;;) {
-                        let s = ASN1.decode(stream);
-                        if (s.tag.isEOC())
-                            break;
-                        sub[sub.length] = s;
+    typeName() {
+        switch (this.tag.tagClass) {
+        case 0: // universal
+            switch (this.tag.tagNumber) {
+            case 0x00: return 'EOC';
+            case 0x01: return 'BOOLEAN';
+            case 0x02: return 'INTEGER';
+            case 0x03: return 'BIT_STRING';
+            case 0x04: return 'OCTET_STRING';
+            case 0x05: return 'NULL';
+            case 0x06: return 'OBJECT_IDENTIFIER';
+            case 0x07: return 'ObjectDescriptor';
+            case 0x08: return 'EXTERNAL';
+            case 0x09: return 'REAL';
+            case 0x0A: return 'ENUMERATED';
+            case 0x0B: return 'EMBEDDED_PDV';
+            case 0x0C: return 'UTF8String';
+            case 0x0D: return 'RELATIVE_OID';
+            case 0x10: return 'SEQUENCE';
+            case 0x11: return 'SET';
+            case 0x12: return 'NumericString';
+            case 0x13: return 'PrintableString'; // ASCII subset
+            case 0x14: return 'TeletexString'; // aka T61String
+            case 0x15: return 'VideotexString';
+            case 0x16: return 'IA5String'; // ASCII
+            case 0x17: return 'UTCTime';
+            case 0x18: return 'GeneralizedTime';
+            case 0x19: return 'GraphicString';
+            case 0x1A: return 'VisibleString'; // ASCII subset
+            case 0x1B: return 'GeneralString';
+            case 0x1C: return 'UniversalString';
+            case 0x1E: return 'BMPString';
+            }
+            return 'Universal_' + this.tag.tagNumber.toString();
+        case 1: return 'Application_' + this.tag.tagNumber.toString();
+        case 2: return '[' + this.tag.tagNumber.toString() + ']'; // Context
+        case 3: return 'Private_' + this.tag.tagNumber.toString();
+        }
+    };
+    /** A string preview of the content (intended for humans). */
+    content(maxLength) {
+        if (this.tag === undefined)
+            return null;
+        if (maxLength === undefined)
+            maxLength = Infinity;
+        let content = this.posContent(),
+            len = Math.abs(this.length);
+        if (!this.tag.isUniversal()) {
+            if (this.sub !== null)
+                return '(' + this.sub.length + ' elem)';
+            let d1 = this.stream.parseOctetString(content, content + len, maxLength);
+            return '(' + d1.size + ' byte)\n' + d1.str;
+        }
+        switch (this.tag.tagNumber) {
+        case 0x01: // BOOLEAN
+            return (this.stream.get(content) === 0) ? 'false' : 'true';
+        case 0x02: // INTEGER
+            return this.stream.parseInteger(content, content + len);
+        case 0x03: { // BIT_STRING
+            let d = recurse(this, 'parseBitString', maxLength);
+            return '(' + d.size + ' bit)\n' + d.str;
+        }
+        case 0x04: { // OCTET_STRING
+            let d = recurse(this, 'parseOctetString', maxLength);
+            return '(' + d.size + ' byte)\n' + d.str;
+        }
+        //case 0x05: // NULL
+        case 0x06: // OBJECT_IDENTIFIER
+            return this.stream.parseOID(content, content + len, maxLength);
+        //case 0x07: // ObjectDescriptor
+        //case 0x08: // EXTERNAL
+        //case 0x09: // REAL
+        case 0x0A: // ENUMERATED
+            return this.stream.parseInteger(content, content + len);
+        //case 0x0B: // EMBEDDED_PDV
+        case 0x0D: // RELATIVE-OID
+            return this.stream.parseRelativeOID(content, content + len, maxLength);
+        case 0x10: // SEQUENCE
+        case 0x11: // SET
+            if (this.sub !== null)
+                return '(' + this.sub.length + ' elem)';
+            else
+                return '(no elem)';
+        case 0x0C: // UTF8String
+            return recurse(this, 'parseStringUTF', maxLength).str;
+        case 0x14: // TeletexString
+            return recurse(this, 'parseStringT61', maxLength).str;
+        case 0x12: // NumericString
+        case 0x13: // PrintableString
+        case 0x15: // VideotexString
+        case 0x16: // IA5String
+        case 0x1A: // VisibleString
+        case 0x1B: // GeneralString
+        //case 0x19: // GraphicString
+        //case 0x1C: // UniversalString
+            return recurse(this, 'parseStringISO', maxLength).str;
+        case 0x1E: // BMPString
+            return recurse(this, 'parseStringBMP', maxLength).str;
+        case 0x17: // UTCTime
+        case 0x18: // GeneralizedTime
+            return this.stream.parseTime(content, content + len, (this.tag.tagNumber == 0x17));
+        }
+        return null;
+    };
+    toString() {
+        return this.typeName() + '@' + this.stream.pos + '[header:' + this.header + ',length:' + this.length + ',sub:' + ((this.sub === null) ? 'null' : this.sub.length) + ']';
+    };
+    toPrettyString(indent) {
+        if (indent === undefined) indent = '';
+        let s = indent + this.typeName() + ' @' + this.stream.pos;
+        if (this.length >= 0)
+            s += '+';
+        s += this.length;
+        if (this.tag.tagConstructed)
+            s += ' (constructed)';
+        else if ((this.tag.isUniversal() && ((this.tag.tagNumber == 0x03) || (this.tag.tagNumber == 0x04))) && (this.sub !== null))
+            s += ' (encapsulates)';
+        let content = this.content();
+        if (content)
+            s += ': ' + content.replace(/\n/g, '|');
+        s += '\n';
+        if (this.sub !== null) {
+            indent += '  ';
+            for (let i = 0, max = this.sub.length; i < max; ++i)
+                s += this.sub[i].toPrettyString(indent);
+        }
+        return s;
+    };
+    posStart() {
+        return this.stream.pos;
+    };
+    posContent() {
+        return this.stream.pos + this.header;
+    };
+    posEnd() {
+        return this.stream.pos + this.header + Math.abs(this.length);
+    };
+    /** Position of the length. */
+    posLen() {
+        return this.stream.pos + this.tagLen;
+    };
+    toHexString() {
+        return this.stream.hexDump(this.posStart(), this.posEnd(), true);
+    };
+    toB64String() {
+        return this.stream.b64Dump(this.posStart(), this.posEnd());
+    };
+    static decodeLength(stream) {
+        let buf = stream.get(),
+            len = buf & 0x7F;
+        if (len == buf) // first bit was 0, short form
+            return len;
+        if (len === 0) // long form with length 0 is a special case
+            return null; // undefined length
+        if (len > 6) // no reason to use Int10, as it would be a huge buffer anyways
+            throw 'Length over 48 bits not supported at position ' + (stream.pos - 1);
+        buf = 0;
+        for (let i = 0; i < len; ++i)
+            buf = (buf * 256) + stream.get();
+        return buf;
+    };
+    static decode(stream, offset) {
+        if (!(stream instanceof Stream))
+            stream = new Stream(stream, offset || 0);
+        let streamStart = new Stream(stream),
+            tag = new ASN1Tag(stream),
+            tagLen = stream.pos - streamStart.pos,
+            len = ASN1.decodeLength(stream),
+            start = stream.pos,
+            header = start - streamStart.pos,
+            sub = null,
+            getSub = function () {
+                sub = [];
+                if (len !== null) {
+                    // definite length
+                    let end = start + len;
+                    if (end > stream.enc.length)
+                        throw 'Container at offset ' + start +  ' has a length of ' + len + ', which is past the end of the stream';
+                    while (stream.pos < end)
+                        sub[sub.length] = ASN1.decode(stream);
+                    if (stream.pos != end)
+                        throw 'Content size is not correct for container at offset ' + start;
+                } else {
+                    // undefined length
+                    try {
+                        for (;;) {
+                            let s = ASN1.decode(stream);
+                            if (s.tag.isEOC())
+                                break;
+                            sub[sub.length] = s;
+                        }
+                        len = start - stream.pos; // undefined lengths are represented as negative values
+                    } catch (e) {
+                        throw 'Exception while decoding undefined length content at offset ' + start + ': ' + e;
                     }
-                    len = start - stream.pos; // undefined lengths are represented as negative values
-                } catch (e) {
-                    throw 'Exception while decoding undefined length content at offset ' + start + ': ' + e;
                 }
-            }
-        };
-    if (tag.tagConstructed) {
-        // must have valid content
-        getSub();
-    } else if (tag.isUniversal() && ((tag.tagNumber == 0x03) || (tag.tagNumber == 0x04))) {
-        // sometimes BitString and OctetString are used to encapsulate ASN.1
-        try {
-            if (tag.tagNumber == 0x03)
-                if (stream.get() != 0)
-                    throw 'BIT STRINGs with unused bits cannot encapsulate.';
+            };
+        if (tag.tagConstructed) {
+            // must have valid content
             getSub();
-            for (let i = 0; i < sub.length; ++i)
-                if (sub[i].tag.isEOC())
-                    throw 'EOC is not supposed to be actual content.';
-        } catch (e) {
-            // but silently ignore when they don't
-            sub = null;
-            //DEBUG console.log('Could not decode structure at ' + start + ':', e);
+        } else if (tag.isUniversal() && ((tag.tagNumber == 0x03) || (tag.tagNumber == 0x04))) {
+            // sometimes BitString and OctetString are used to encapsulate ASN.1
+            try {
+                if (tag.tagNumber == 0x03)
+                    if (stream.get() != 0)
+                        throw 'BIT STRINGs with unused bits cannot encapsulate.';
+                getSub();
+                for (let i = 0; i < sub.length; ++i)
+                    if (sub[i].tag.isEOC())
+                        throw 'EOC is not supposed to be actual content.';
+            } catch (e) {
+                // but silently ignore when they don't
+                sub = null;
+                //DEBUG console.log('Could not decode structure at ' + start + ':', e);
+            }
+        }
+        if (sub === null) {
+            if (len === null)
+                throw "We can't skip over an invalid tag with undefined length at offset " + start;
+            stream.pos = start + Math.abs(len);
+        }
+        return new ASN1(streamStart, header, len, tag, tagLen, sub);
+    };
+
+}
+
+class ASN1Tag {
+    constructor(stream) {
+        let buf = stream.get();
+        this.tagClass = buf >> 6;
+        this.tagConstructed = ((buf & 0x20) !== 0);
+        this.tagNumber = buf & 0x1F;
+        if (this.tagNumber == 0x1F) { // long tag
+            let n = new Int10();
+            do {
+                buf = stream.get();
+                n.mulAdd(128, buf & 0x7F);
+            } while (buf & 0x80);
+            this.tagNumber = n.simplify();
         }
     }
-    if (sub === null) {
-        if (len === null)
-            throw "We can't skip over an invalid tag with undefined length at offset " + start;
-        stream.pos = start + Math.abs(len);
-    }
-    return new ASN1(streamStart, header, len, tag, tagLen, sub);
-};
+    isUniversal() {
+        return this.tagClass === 0x00;
+    };
+    isEOC() {
+        return this.tagClass === 0x00 && this.tagNumber === 0x00;
+    };
+}
 
 return ASN1;
 
diff --git a/base64.js b/base64.js
index fb9892e..7208f5b 100644
--- a/base64.js
+++ b/base64.js
@@ -20,89 +20,92 @@
 'use strict';
 
 const
-    Base64 = {},
     haveU8 = (typeof Uint8Array == 'function');
 
 let decoder; // populated on first usage
 
-Base64.decode = function (a) {
-    let isString = (typeof a == 'string');
-    let i;
-    if (decoder === undefined) {
-        let b64 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/',
-            ignore = '= \f\n\r\t\u00A0\u2028\u2029';
-        decoder = [];
-        for (i = 0; i < 64; ++i)
-            decoder[b64.charCodeAt(i)] = i;
-        for (i = 0; i < ignore.length; ++i)
-            decoder[ignore.charCodeAt(i)] = -1;
-        // RFC 3548 URL & file safe encoding
-        decoder['-'.charCodeAt(0)] = decoder['+'.charCodeAt(0)];
-        decoder['_'.charCodeAt(0)] = decoder['/'.charCodeAt(0)];
-    }
-    let out = haveU8 ? new Uint8Array(a.length * 3 >> 2) : [];
-    let bits = 0, char_count = 0, len = 0;
-    for (i = 0; i < a.length; ++i) {
-        let c = isString ? a.charCodeAt(i) : a[i];
-        if (c == 61) // '='.charCodeAt(0)
+class Base64 {
+
+    static decode(a) {
+        let isString = (typeof a == 'string');
+        let i;
+        if (decoder === undefined) {
+            let b64 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/',
+                ignore = '= \f\n\r\t\u00A0\u2028\u2029';
+            decoder = [];
+            for (i = 0; i < 64; ++i)
+                decoder[b64.charCodeAt(i)] = i;
+            for (i = 0; i < ignore.length; ++i)
+                decoder[ignore.charCodeAt(i)] = -1;
+            // RFC 3548 URL & file safe encoding
+            decoder['-'.charCodeAt(0)] = decoder['+'.charCodeAt(0)];
+            decoder['_'.charCodeAt(0)] = decoder['/'.charCodeAt(0)];
+        }
+        let out = haveU8 ? new Uint8Array(a.length * 3 >> 2) : [];
+        let bits = 0, char_count = 0, len = 0;
+        for (i = 0; i < a.length; ++i) {
+            let c = isString ? a.charCodeAt(i) : a[i];
+            if (c == 61) // '='.charCodeAt(0)
+                break;
+            c = decoder[c];
+            if (c == -1)
+                continue;
+            if (c === undefined)
+                throw 'Illegal character at offset ' + i;
+            bits |= c;
+            if (++char_count >= 4) {
+                out[len++] = (bits >> 16);
+                out[len++] = (bits >> 8) & 0xFF;
+                out[len++] = bits & 0xFF;
+                bits = 0;
+                char_count = 0;
+            } else {
+                bits <<= 6;
+            }
+        }
+        switch (char_count) {
+        case 1:
+            throw 'Base64 encoding incomplete: at least 2 bits missing';
+        case 2:
+            out[len++] = (bits >> 10);
             break;
-        c = decoder[c];
-        if (c == -1)
-            continue;
-        if (c === undefined)
-            throw 'Illegal character at offset ' + i;
-        bits |= c;
-        if (++char_count >= 4) {
+        case 3:
             out[len++] = (bits >> 16);
             out[len++] = (bits >> 8) & 0xFF;
-            out[len++] = bits & 0xFF;
-            bits = 0;
-            char_count = 0;
-        } else {
-            bits <<= 6;
+            break;
         }
-    }
-    switch (char_count) {
-    case 1:
-        throw 'Base64 encoding incomplete: at least 2 bits missing';
-    case 2:
-        out[len++] = (bits >> 10);
-        break;
-    case 3:
-        out[len++] = (bits >> 16);
-        out[len++] = (bits >> 8) & 0xFF;
-        break;
-    }
-    if (haveU8 && out.length > len) // in case it was originally longer because of ignored characters
-        out = out.subarray(0, len);
-    return out;
-};
+        if (haveU8 && out.length > len) // in case it was originally longer because of ignored characters
+            out = out.subarray(0, len);
+        return out;
+    };
+
+    static pretty(str) {
+        // fix padding
+        if (str.length % 4 > 0)
+            str = (str + '===').slice(0, str.length + str.length % 4);
+        // convert RFC 3548 to standard Base64
+        str = str.replace(/-/g, '+').replace(/_/g, '/');
+        // 80 column width
+        return str.replace(/(.{80})/g, '$1\n');
+    };
 
-Base64.pretty = function (str) {
-    // fix padding
-    if (str.length % 4 > 0)
-        str = (str + '===').slice(0, str.length + str.length % 4);
-    // convert RFC 3548 to standard Base64
-    str = str.replace(/-/g, '+').replace(/_/g, '/');
-    // 80 column width
-    return str.replace(/(.{80})/g, '$1\n');
-};
+    static re = /-----BEGIN [^-]+-----([A-Za-z0-9+/=\s]+)-----END [^-]+-----|begin-base64[^\n]+\n([A-Za-z0-9+/=\s]+)====|^([A-Za-z0-9+/=\s]+)$/;
+    static unarmor(a) {
+        let m = Base64.re.exec(a);
+        if (m) {
+            if (m[1])
+                a = m[1];
+            else if (m[2])
+                a = m[2];
+            else if (m[3])
+                a = m[3];
+            else
+                throw 'RegExp out of sync';
+        }
+        return Base64.decode(a);
+    };
 
-Base64.re = /-----BEGIN [^-]+-----([A-Za-z0-9+/=\s]+)-----END [^-]+-----|begin-base64[^\n]+\n([A-Za-z0-9+/=\s]+)====|^([A-Za-z0-9+/=\s]+)$/;
-Base64.unarmor = function (a) {
-    let m = Base64.re.exec(a);
-    if (m) {
-        if (m[1])
-            a = m[1];
-        else if (m[2])
-            a = m[2];
-        else if (m[3])
-            a = m[3];
-        else
-            throw 'RegExp out of sync';
-    }
-    return Base64.decode(a);
-};
+}
 
 return Base64;
 
diff --git a/int10.js b/int10.js
index c80cd41..ad1c5be 100644
--- a/int10.js
+++ b/int10.js
@@ -1,5 +1,5 @@
 // Big integer base-10 printing library
-// Copyright (c) 2008-2022 Lapo Luchini <lapo@lapo.it>
+// Copyright (c) 2008-2023 Lapo Luchini <lapo@lapo.it>
 
 // Permission to use, copy, modify, and/or distribute this software for any
 // purpose with or without fee is hereby granted, provided that the above
@@ -21,92 +21,95 @@
 
 let max = 10000000000000; // biggest 10^n integer that can still fit 2^53 when multiplied by 256
 
-/**
- * Arbitrary length base-10 value.
- * @param {number} value - Optional initial value (will be 0 otherwise).
- */
-function Int10(value) {
-    this.buf = [+value || 0];
-}
+class Int10 {
+    /**
+     * Arbitrary length base-10 value.
+     * @param {number} value - Optional initial value (will be 0 otherwise).
+     */
+    constructor(value) {
+        this.buf = [+value || 0];
+    }
 
-/**
- * Multiply value by m and add c.
- * @param {number} m - multiplier, must be < =256
- * @param {number} c - value to add
- */
-Int10.prototype.mulAdd = function (m, c) {
-    // assert(m <= 256)
-    let b = this.buf,
-        l = b.length,
-        i, t;
-    for (i = 0; i < l; ++i) {
-        t = b[i] * m + c;
-        if (t < max)
-            c = 0;
-        else {
-            c = 0|(t / max);
-            t -= c * max;
+    /**
+     * Multiply value by m and add c.
+     * @param {number} m - multiplier, must be < =256
+     * @param {number} c - value to add
+     */
+    mulAdd(m, c) {
+        // assert(m <= 256)
+        let b = this.buf,
+            l = b.length,
+            i, t;
+        for (i = 0; i < l; ++i) {
+            t = b[i] * m + c;
+            if (t < max)
+                c = 0;
+            else {
+                c = 0|(t / max);
+                t -= c * max;
+            }
+            b[i] = t;
         }
-        b[i] = t;
-    }
-    if (c > 0)
-        b[i] = c;
-};
+        if (c > 0)
+            b[i] = c;
+    };
 
-/**
- * Subtract value.
- * @param {number} c - value to subtract
- */
-Int10.prototype.sub = function (c) {
-    let b = this.buf,
-        l = b.length,
-        i, t;
-    for (i = 0; i < l; ++i) {
-        t = b[i] - c;
-        if (t < 0) {
-            t += max;
-            c = 1;
-        } else
-            c = 0;
-        b[i] = t;
-    }
-    while (b[b.length - 1] === 0)
-        b.pop();
-};
+    /**
+     * Subtract value.
+     * @param {number} c - value to subtract
+     */
+    sub(c) {
+        let b = this.buf,
+            l = b.length,
+            i, t;
+        for (i = 0; i < l; ++i) {
+            t = b[i] - c;
+            if (t < 0) {
+                t += max;
+                c = 1;
+            } else
+                c = 0;
+            b[i] = t;
+        }
+        while (b[b.length - 1] === 0)
+            b.pop();
+    };
+
+    /**
+     * Convert to decimal string representation.
+     * @param {*} base - optional value, only value accepted is 10
+     */
+    toString(base) {
+        if ((base || 10) != 10)
+            throw 'only base 10 is supported';
+        let b = this.buf,
+            s = b[b.length - 1].toString();
+        for (let i = b.length - 2; i >= 0; --i)
+            s += (max + b[i]).toString().substring(1);
+        return s;
+    };
 
-/**
- * Convert to decimal string representation.
- * @param {*} base - optional value, only value accepted is 10
- */
-Int10.prototype.toString = function (base) {
-    if ((base || 10) != 10)
-        throw 'only base 10 is supported';
-    let b = this.buf,
-        s = b[b.length - 1].toString();
-    for (let i = b.length - 2; i >= 0; --i)
-        s += (max + b[i]).toString().substring(1);
-    return s;
-};
+    /**
+     * Convert to Number value representation.
+     * Will probably overflow 2^53 and thus become approximate.
+     */
+    valueOf() {
+        let b = this.buf,
+            v = 0;
+        for (let i = b.length - 1; i >= 0; --i)
+            v = v * max + b[i];
+        return v;
+    };
 
-/**
- * Convert to Number value representation.
- * Will probably overflow 2^53 and thus become approximate.
- */
-Int10.prototype.valueOf = function () {
-    let b = this.buf,
-        v = 0;
-    for (let i = b.length - 1; i >= 0; --i)
-        v = v * max + b[i];
-    return v;
-};
+    /**
+     * Return value as a simple Number (if it is <= 10000000000000), or return this.
+     */
+    simplify() {
+        let b = this.buf;
+        return (b.length == 1) ? b[0] : this;
+    };
 
-/**
- * Return value as a simple Number (if it is <= 10000000000000), or return this.
- */
-Int10.prototype.simplify = function () {
-    let b = this.buf;
-    return (b.length == 1) ? b[0] : this;
-};
+}
 
 return Int10;