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Created September 7, 2012 00:18
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Hogan.js 3.0
/*
* Copyright 2011 Twitter, Inc.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
var Hogan = {};
(function (Hogan, useArrayBuffer) {
Hogan.Template = function (codeObj, text, compiler, options) {
codeObj = codeObj || {};
this.r = codeObj.code || this.r;
this.c = compiler;
this.options = options;
this.text = text || '';
this.partials = codeObj.partials || {};
this.subs = codeObj.subs || {};
this.ib();
}
Hogan.Template.prototype = {
// render: replaced by generated code.
r: function (context, partials, indent) { return ''; },
// variable escaping
v: hoganEscape,
// triple stache
t: coerceToString,
render: function render(context, partials, indent) {
return this.ri([context], partials || {}, indent);
},
// render internal -- a hook for overrides that catches partials too
ri: function (context, partials, indent) {
return this.r(context, partials, indent);
},
// ensurePartial
ep: function(symbol, partials) {
var partial = this.partials[symbol];
// check to see that if we've instantiated this partial before
var template = partials[partial.name];
if (partial.instance && partial.base == template) {
return partial.instance;
}
if (typeof template == 'string') {
if (!this.c) {
throw new Error("No compiler available.");
}
template = this.c.compile(template, this.options);
}
if (!template) {
return null;
}
// We use this to check whether the partials dictionary has changed
this.partials[symbol].base = template;
if (partial.subs) {
template = createSpecializedPartial(template, partial.subs, partial.partials, this.text);
}
this.partials[symbol].instance = template;
return template;
},
// tries to find a partial in the curent scope and render it
rp: function(symbol, context, partials, indent) {
var partial = this.ep(symbol, partials);
if (!partial) {
return '';
}
return partial.ri(context, partials, indent);
},
// render a section
rs: function(context, partials, section) {
var tail = context[context.length - 1];
if (!isArray(tail)) {
section(context, partials, this);
return;
}
for (var i = 0; i < tail.length; i++) {
context.push(tail[i]);
section(context, partials, this);
context.pop();
}
},
// maybe start a section
s: function(val, ctx, partials, inverted, start, end, tags) {
var pass;
if (isArray(val) && val.length === 0) {
return false;
}
if (typeof val == 'function') {
val = this.ms(val, ctx, partials, inverted, start, end, tags);
}
pass = (val === '') || !!val;
if (!inverted && pass && ctx) {
ctx.push((typeof val == 'object') ? val : ctx[ctx.length - 1]);
}
return pass;
},
// find values with dotted names
d: function(key, ctx, partials, returnFound) {
var names = key.split('.'),
val = this.f(names[0], ctx, partials, returnFound),
cx = null;
if (key === '.' && isArray(ctx[ctx.length - 2])) {
val = ctx[ctx.length - 1];
} else {
for (var i = 1; i < names.length; i++) {
if (val && typeof val == 'object' && val[names[i]] != null) {
cx = val;
val = val[names[i]];
} else {
val = '';
}
}
}
if (returnFound && !val) {
return false;
}
if (!returnFound && typeof val == 'function') {
ctx.push(cx);
val = this.mv(val, ctx, partials);
ctx.pop();
}
return val;
},
// find values with normal names
f: function(key, ctx, partials, returnFound) {
var val = false,
v = null,
found = false;
for (var i = ctx.length - 1; i >= 0; i--) {
v = ctx[i];
if (v && typeof v == 'object' && v[key] != null) {
val = v[key];
found = true;
break;
}
}
if (!found) {
return (returnFound) ? false : "";
}
if (!returnFound && typeof val == 'function') {
val = this.mv(val, ctx, partials);
}
return val;
},
// higher order templates
ls: function(func, cx, partials, text, tags) {
var oldTags = this.options.delimiters;
this.options.delimiters = tags;
this.b(this.ct(coerceToString(func.call(cx, text)), cx, partials));
this.options.delimiters = oldTags;
return false;
},
// compile text
ct: function(text, cx, partials) {
if (this.options.disableLambda) {
throw new Error('Lambda features disabled.');
}
return this.c.compile(text, this.options).render(cx, partials);
},
// template result buffering
b: (useArrayBuffer) ? function(s) { this.buf.push(s); } :
function(s) { this.buf += s; },
fl: (useArrayBuffer) ? function() { var r = this.buf.join(''); this.buf = []; return r; } :
function() { var r = this.buf; this.buf = ''; return r; },
// init the buffer
ib: function () {
this.buf = (useArrayBuffer) ? [] : '';
},
// method replace section
ms: function(func, ctx, partials, inverted, start, end, tags) {
var textSource,
cx = ctx[ctx.length - 1],
result = func.call(cx);
if (typeof result == 'function') {
if (inverted) {
return true;
} else {
textSource = (this.activeSub && this.subsText[this.activeSub]) ? this.subsText[this.activeSub] : this.text;
return this.ls(result, cx, partials, textSource.substring(start, end), tags);
}
}
return result;
},
// method replace variable
mv: function(func, ctx, partials) {
var cx = ctx[ctx.length - 1];
var result = func.call(cx);
if (typeof result == 'function') {
return this.ct(coerceToString(result.call(cx)), cx, partials);
}
return result;
},
sub: function(name, context, partials, indent) {
var f = this.subs[name];
if (f) {
this.activeSub = name;
f(context, partials, this, indent);
this.activeSub = false;
}
}
};
function createSpecializedPartial(instance, subs, partials, childText) {
function PartialTemplate() {};
PartialTemplate.prototype = instance;
function Substitutions() {};
Substitutions.prototype = instance.subs;
var key;
var partial = new PartialTemplate();
partial.subs = new Substitutions();
partial.subsText = {}; //hehe. substext.
partial.ib();
for (key in subs) {
partial.subs[key] = subs[key];
partial.subsText[key] = childText;
}
for (key in partials) {
partial.partials[key] = partials[key];
}
return partial;
}
var rAmp = /&/g,
rLt = /</g,
rGt = />/g,
rApos =/\'/g,
rQuot = /\"/g,
hChars =/[&<>\"\']/;
function coerceToString(val) {
return String((val === null || val === undefined) ? '' : val);
}
function hoganEscape(str) {
str = coerceToString(str);
return hChars.test(str) ?
str
.replace(rAmp,'&amp;')
.replace(rLt,'&lt;')
.replace(rGt,'&gt;')
.replace(rApos,'&#39;')
.replace(rQuot, '&quot;') :
str;
}
var isArray = Array.isArray || function(a) {
return Object.prototype.toString.call(a) === '[object Array]';
};
})(typeof exports !== 'undefined' ? exports : Hogan);
(function (Hogan) {
// Setup regex assignments
// remove whitespace according to Mustache spec
var rIsWhitespace = /\S/,
rQuot = /\"/g,
rNewline = /\n/g,
rCr = /\r/g,
rSlash = /\\/g;
Hogan.tags = {
'#': 1, '^': 2, '<': 3, '$': 4,
'/': 5, '!': 6, '>': 7, '=': 8, '_v': 9,
'{': 10, '&': 11, '_t': 12
};
Hogan.scan = function scan(text, delimiters) {
var len = text.length,
IN_TEXT = 0,
IN_TAG_TYPE = 1,
IN_TAG = 2,
state = IN_TEXT,
tagType = null,
tag = null,
buf = '',
tokens = [],
seenTag = false,
i = 0,
lineStart = 0,
otag = '{{',
ctag = '}}';
function addBuf() {
if (buf.length > 0) {
tokens.push({tag: '_t', text: new String(buf)});
buf = '';
}
}
function lineIsWhitespace() {
var isAllWhitespace = true;
for (var j = lineStart; j < tokens.length; j++) {
isAllWhitespace =
(Hogan.tags[tokens[j].tag] < Hogan.tags['_v']) ||
(tokens[j].tag == '_t' && tokens[j].text.match(rIsWhitespace) === null);
if (!isAllWhitespace) {
return false;
}
}
return isAllWhitespace;
}
function filterLine(haveSeenTag, noNewLine) {
addBuf();
if (haveSeenTag && lineIsWhitespace()) {
for (var j = lineStart, next; j < tokens.length; j++) {
if (tokens[j].text) {
if ((next = tokens[j+1]) && next.tag == '>') {
// set indent to token value
next.indent = tokens[j].text.toString()
}
tokens.splice(j, 1);
}
}
} else if (!noNewLine) {
tokens.push({tag:'\n'});
}
seenTag = false;
lineStart = tokens.length;
}
function changeDelimiters(text, index) {
var close = '=' + ctag,
closeIndex = text.indexOf(close, index),
delimiters = trim(
text.substring(text.indexOf('=', index) + 1, closeIndex)
).split(' ');
otag = delimiters[0];
ctag = delimiters[1];
return closeIndex + close.length - 1;
}
if (delimiters) {
delimiters = delimiters.split(' ');
otag = delimiters[0];
ctag = delimiters[1];
}
for (i = 0; i < len; i++) {
if (state == IN_TEXT) {
if (tagChange(otag, text, i)) {
--i;
addBuf();
state = IN_TAG_TYPE;
} else {
if (text.charAt(i) == '\n') {
filterLine(seenTag);
} else {
buf += text.charAt(i);
}
}
} else if (state == IN_TAG_TYPE) {
i += otag.length - 1;
tag = Hogan.tags[text.charAt(i + 1)];
tagType = tag ? text.charAt(i + 1) : '_v';
if (tagType == '=') {
i = changeDelimiters(text, i);
state = IN_TEXT;
} else {
if (tag) {
i++;
}
state = IN_TAG;
}
seenTag = i;
} else {
if (tagChange(ctag, text, i)) {
tokens.push({tag: tagType, n: trim(buf), otag: otag, ctag: ctag,
i: (tagType == '/') ? seenTag - otag.length : i + ctag.length});
buf = '';
i += ctag.length - 1;
state = IN_TEXT;
if (tagType == '{') {
if (ctag == '}}') {
i++;
} else {
cleanTripleStache(tokens[tokens.length - 1]);
}
}
} else {
buf += text.charAt(i);
}
}
}
filterLine(seenTag, true);
return tokens;
}
function cleanTripleStache(token) {
if (token.n.substr(token.n.length - 1) === '}') {
token.n = token.n.substring(0, token.n.length - 1);
}
}
function trim(s) {
if (s.trim) {
return s.trim();
}
return s.replace(/^\s*|\s*$/g, '');
}
function tagChange(tag, text, index) {
if (text.charAt(index) != tag.charAt(0)) {
return false;
}
for (var i = 1, l = tag.length; i < l; i++) {
if (text.charAt(index + i) != tag.charAt(i)) {
return false;
}
}
return true;
}
// the tags allowed inside super templates
var allowedInSuper = {'_t': true, '\n': true, '$': true, '/': true};
function buildTree(tokens, kind, stack, customTags) {
var instructions = [],
opener = null,
tail = null,
token = null;
tail = stack[stack.length - 1];
while (tokens.length > 0) {
token = tokens.shift();
if (tail && tail.tag == '<' && !(token.tag in allowedInSuper)) {
throw new Error('Illegal content in < super tag.');
}
if (Hogan.tags[token.tag] <= Hogan.tags['$'] || isOpener(token, customTags)) {
stack.push(token);
token.nodes = buildTree(tokens, token.tag, stack, customTags);
} else if (token.tag == '/') {
if (stack.length === 0) {
throw new Error('Closing tag without opener: /' + token.n);
}
opener = stack.pop();
if (token.n != opener.n && !isCloser(token.n, opener.n, customTags)) {
throw new Error('Nesting error: ' + opener.n + ' vs. ' + token.n);
}
opener.end = token.i;
return instructions;
} else if (token.tag == '\n') {
token.last = (tokens.length == 0) || (tokens[0].tag == '\n');
}
instructions.push(token);
}
if (stack.length > 0) {
throw new Error('missing closing tag: ' + stack.pop().n);
}
return instructions;
}
function isOpener(token, tags) {
for (var i = 0, l = tags.length; i < l; i++) {
if (tags[i].o == token.n) {
token.tag = '#';
return true;
}
}
}
function isCloser(close, open, tags) {
for (var i = 0, l = tags.length; i < l; i++) {
if (tags[i].c == close && tags[i].o == open) {
return true;
}
}
}
function stringifySubstitutions(obj) {
var items = [];
for (var key in obj) {
items.push('"' + esc(key) + '": function(c,p,t,i) {' + obj[key] + '}');
}
return "{ " + items.join(",") + " }";
}
function stringifyPartials(codeObj) {
var partials = [];
for (var key in codeObj.partials) {
partials.push('"' + esc(key) + '":{name:"' + esc(codeObj.partials[key].name) + '", ' + stringifyPartials(codeObj.partials[key]) + "}");
}
return "partials: {" + partials.join(",") + "}, subs: " + stringifySubstitutions(codeObj.subs);
}
Hogan.stringify = function(codeObj, text, options) {
return "{code: function (c,p,i) { " + Hogan.wrapMain(codeObj.code) + " }," + stringifyPartials(codeObj) + "}";
}
var serialNo = 0;
Hogan.generate = function(tree, text, options) {
serialNo = 0;
var context = { code: '', subs: {}, partials: {} };
Hogan.walk(tree, context);
if (options.asString) {
return this.stringify(context, text, options);
}
return this.makeTemplate(context, text, options);
}
Hogan.wrapMain = function(code) {
return 'var t=this;t.b(i=i||"");' + code + 'return t.fl();';
}
Hogan.template = Hogan.Template;
Hogan.makeTemplate = function(codeObj, text, options) {
var template = this.makePartials(codeObj);
template.code = new Function('c', 'p', 'i', this.wrapMain(codeObj.code));
return new this.template(template, text, this, options);
}
Hogan.makePartials = function(codeObj) {
var key, template = {subs: {}, partials: codeObj.partials, name: codeObj.name};
for (key in template.partials) {
template.partials[key] = this.makePartials(template.partials[key]);
}
for (key in codeObj.subs) {
template.subs[key] = new Function('c', 'p', 't', 'i', codeObj.subs[key]);
}
return template;
}
function esc(s) {
return s.replace(rSlash, '\\\\')
.replace(rQuot, '\\\"')
.replace(rNewline, '\\n')
.replace(rCr, '\\r');
}
function chooseMethod(s) {
return (~s.indexOf('.')) ? 'd' : 'f';
}
function createPartial(node, context) {
var prefix = "<" + (context.prefix || "");
var sym = prefix + node.n + serialNo++;
context.partials[sym] = {name: node.n, partials: {}};
context.code += 't.b(t.rp("' + esc(sym) + '",c,p,"' + (node.indent || '') + '"));';
return sym;
}
Hogan.codegen = {
'#': function(node, context) {
context.code += 'if(t.s(t.' + chooseMethod(node.n) + '("' + esc(node.n) + '",c,p,1),' +
'c,p,0,' + node.i + ',' + node.end + ',"' + node.otag + " " + node.ctag + '")){' +
't.rs(c,p,' + 'function(c,p,t){';
Hogan.walk(node.nodes, context);
context.code += '});c.pop();}';
},
'^': function(node, context) {
context.code += 'if(!t.s(t.' + chooseMethod(node.n) + '("' + esc(node.n) + '",c,p,1),c,p,1,0,0,"")){';
Hogan.walk(node.nodes, context);
context.code += '};';
},
'>': createPartial,
'<': function(node, context) {
var ctx = {partials: {}, code: '', subs: {}, inPartial: true};
Hogan.walk(node.nodes, ctx);
var template = context.partials[createPartial(node, context)];
template.subs = ctx.subs;
template.partials = ctx.partials;
},
'$': function(node, context) {
var ctx = {subs: {}, code: '', partials: context.partials, prefix: node.n};
Hogan.walk(node.nodes, ctx);
context.subs[node.n] = ctx.code;
if (!context.inPartial) {
context.code += 't.sub("' + esc(node.n) + '",c,p,i);';
}
},
'\n': function(node, context) {
context.code += write('"\\n"' + (node.last ? '' : ' + i'));
},
'_v': function(node, context) {
context.code += 't.b(t.v(t.' + chooseMethod(node.n) + '("' + esc(node.n) + '",c,p,0)));';
},
'_t': function(node, context) {
context.code += write('"' + esc(node.text) + '"');
},
'{': tripleStache,
'&': tripleStache
}
function tripleStache(node, context) {
context.code += 't.b(t.t(t.' + chooseMethod(node.n) + '("' + esc(node.n) + '",c,p,0)));';
}
function write(s) {
return 't.b(' + s + ');';
}
Hogan.walk = function (nodelist, context) {
var func;
for (var i = 0, l = nodelist.length; i < l; i++) {
func = Hogan.codegen[nodelist[i].tag];
func && func(nodelist[i], context);
}
return context;
}
Hogan.parse = function(tokens, text, options) {
options = options || {};
return buildTree(tokens, '', [], options.sectionTags || []);
},
Hogan.cache = {};
Hogan.cacheKey = function(text, options) {
return [text, !!options.asString, !!options.disableLambda].join('||');
},
Hogan.compile = function(text, options) {
options = options || {};
var key = Hogan.cacheKey(text, options);
var template = this.cache[key];
if (template) {
return template;
}
template = this.generate(this.parse(this.scan(text, options.delimiters), text, options), text, options);
return this.cache[key] = template;
};
})(typeof exports !== 'undefined' ? exports : Hogan);
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