pegjs/lib/compiler/passes/generate-js.js
David Majda 5a4d04fa90 Construct expectations using functions
Until now, expectations were constructed using object literals. This
commit changes the construction to use factory functions.

This change makes generated parsers slightly smaller because property
names don't have to be repeated many times and factory function calls
are more amenable to minifying.

Some numbers based on the aggregate size of parsers generated from
examples/*.pegjs:

  Optimization   Minified?   Size before   Size after   Saving
  ------------------------------------------------------------
  speed          no               719066       716063    0.42%
  speed          yes              188998       180202    4.65%
  size           no               194810       197813    1.52%
  size           yes              108782        99947    8.12%

(Minification was done using "uglify --mangle --compress" with
uglify-js 2.4.24.)
2016-06-18 06:57:09 +02:00

1320 lines
41 KiB
JavaScript

"use strict";
var arrays = require("../../utils/arrays"),
objects = require("../../utils/objects"),
asts = require("../asts"),
op = require("../opcodes"),
js = require("../js");
/* Generates parser JavaScript code. */
function generateJS(ast, options) {
/* These only indent non-empty lines to avoid trailing whitespace. */
function indent2(code) { return code.replace(/^(.+)$/gm, ' $1'); }
function indent6(code) { return code.replace(/^(.+)$/gm, ' $1'); }
function indent10(code) { return code.replace(/^(.+)$/gm, ' $1'); }
function generateTables() {
if (options.optimize === "size") {
return [
'peg$consts = [',
indent2(ast.consts.join(',\n')),
'],',
'',
'peg$bytecode = [',
indent2(arrays.map(ast.rules, function(rule) {
return 'peg$decode("'
+ js.stringEscape(arrays.map(
rule.bytecode,
function(b) { return String.fromCharCode(b + 32); }
).join(''))
+ '")';
}).join(',\n')),
'],'
].join('\n');
} else {
return arrays.map(
ast.consts,
function(c, i) { return 'peg$c' + i + ' = ' + c + ','; }
).join('\n');
}
}
function generateRuleHeader(ruleNameCode, ruleIndexCode) {
var parts = [];
parts.push('');
if (options.trace) {
parts.push([
'peg$tracer.trace({',
' type: "rule.enter",',
' rule: ' + ruleNameCode + ',',
' location: peg$computeLocation(startPos, startPos)',
'});',
''
].join('\n'));
}
if (options.cache) {
parts.push([
'var key = peg$currPos * ' + ast.rules.length + ' + ' + ruleIndexCode + ',',
' cached = peg$resultsCache[key];',
'',
'if (cached) {',
' peg$currPos = cached.nextPos;',
''
].join('\n'));
if (options.trace) {
parts.push([
'if (cached.result !== peg$FAILED) {',
' peg$tracer.trace({',
' type: "rule.match",',
' rule: ' + ruleNameCode + ',',
' result: cached.result,',
' location: peg$computeLocation(startPos, peg$currPos)',
' });',
'} else {',
' peg$tracer.trace({',
' type: "rule.fail",',
' rule: ' + ruleNameCode + ',',
' location: peg$computeLocation(startPos, startPos)',
' });',
'}',
''
].join('\n'));
}
parts.push([
' return cached.result;',
'}',
''
].join('\n'));
}
return parts.join('\n');
}
function generateRuleFooter(ruleNameCode, resultCode) {
var parts = [];
if (options.cache) {
parts.push([
'',
'peg$resultsCache[key] = { nextPos: peg$currPos, result: ' + resultCode + ' };'
].join('\n'));
}
if (options.trace) {
parts.push([
'',
'if (' + resultCode + ' !== peg$FAILED) {',
' peg$tracer.trace({',
' type: "rule.match",',
' rule: ' + ruleNameCode + ',',
' result: ' + resultCode + ',',
' location: peg$computeLocation(startPos, peg$currPos)',
' });',
'} else {',
' peg$tracer.trace({',
' type: "rule.fail",',
' rule: ' + ruleNameCode + ',',
' location: peg$computeLocation(startPos, startPos)',
' });',
'}'
].join('\n'));
}
parts.push([
'',
'return ' + resultCode + ';'
].join('\n'));
return parts.join('\n');
}
function generateInterpreter() {
var parts = [];
function generateCondition(cond, argsLength) {
var baseLength = argsLength + 3,
thenLengthCode = 'bc[ip + ' + (baseLength - 2) + ']',
elseLengthCode = 'bc[ip + ' + (baseLength - 1) + ']';
return [
'ends.push(end);',
'ips.push(ip + ' + baseLength + ' + ' + thenLengthCode + ' + ' + elseLengthCode + ');',
'',
'if (' + cond + ') {',
' end = ip + ' + baseLength + ' + ' + thenLengthCode + ';',
' ip += ' + baseLength + ';',
'} else {',
' end = ip + ' + baseLength + ' + ' + thenLengthCode + ' + ' + elseLengthCode + ';',
' ip += ' + baseLength + ' + ' + thenLengthCode + ';',
'}',
'',
'break;'
].join('\n');
}
function generateLoop(cond) {
var baseLength = 2,
bodyLengthCode = 'bc[ip + ' + (baseLength - 1) + ']';
return [
'if (' + cond + ') {',
' ends.push(end);',
' ips.push(ip);',
'',
' end = ip + ' + baseLength + ' + ' + bodyLengthCode + ';',
' ip += ' + baseLength + ';',
'} else {',
' ip += ' + baseLength + ' + ' + bodyLengthCode + ';',
'}',
'',
'break;'
].join('\n');
}
function generateCall() {
var baseLength = 4,
paramsLengthCode = 'bc[ip + ' + (baseLength - 1) + ']';
return [
'params = bc.slice(ip + ' + baseLength + ', ip + ' + baseLength + ' + ' + paramsLengthCode + ');',
'for (i = 0; i < ' + paramsLengthCode + '; i++) {',
' params[i] = stack[stack.length - 1 - params[i]];',
'}',
'',
'stack.splice(',
' stack.length - bc[ip + 2],',
' bc[ip + 2],',
' peg$consts[bc[ip + 1]].apply(null, params)',
');',
'',
'ip += ' + baseLength + ' + ' + paramsLengthCode + ';',
'break;'
].join('\n');
}
parts.push([
'function peg$decode(s) {',
' var bc = new Array(s.length), i;',
'',
' for (i = 0; i < s.length; i++) {',
' bc[i] = s.charCodeAt(i) - 32;',
' }',
'',
' return bc;',
'}',
'',
'function peg$parseRule(index) {'
].join('\n'));
if (options.trace) {
parts.push([
' var bc = peg$bytecode[index],',
' ip = 0,',
' ips = [],',
' end = bc.length,',
' ends = [],',
' stack = [],',
' startPos = peg$currPos,',
' params, i;'
].join('\n'));
} else {
parts.push([
' var bc = peg$bytecode[index],',
' ip = 0,',
' ips = [],',
' end = bc.length,',
' ends = [],',
' stack = [],',
' params, i;'
].join('\n'));
}
parts.push(indent2(generateRuleHeader('peg$ruleNames[index]', 'index')));
parts.push([
/*
* The point of the outer loop and the |ips| & |ends| stacks is to avoid
* recursive calls for interpreting parts of bytecode. In other words, we
* implement the |interpret| operation of the abstract machine without
* function calls. Such calls would likely slow the parser down and more
* importantly cause stack overflows for complex grammars.
*/
' while (true) {',
' while (ip < end) {',
' switch (bc[ip]) {',
' case ' + op.PUSH + ':', // PUSH c
' stack.push(peg$consts[bc[ip + 1]]);',
' ip += 2;',
' break;',
'',
' case ' + op.PUSH_UNDEFINED + ':', // PUSH_UNDEFINED
' stack.push(void 0);',
' ip++;',
' break;',
'',
' case ' + op.PUSH_NULL + ':', // PUSH_NULL
' stack.push(null);',
' ip++;',
' break;',
'',
' case ' + op.PUSH_FAILED + ':', // PUSH_FAILED
' stack.push(peg$FAILED);',
' ip++;',
' break;',
'',
' case ' + op.PUSH_EMPTY_ARRAY + ':', // PUSH_EMPTY_ARRAY
' stack.push([]);',
' ip++;',
' break;',
'',
' case ' + op.PUSH_CURR_POS + ':', // PUSH_CURR_POS
' stack.push(peg$currPos);',
' ip++;',
' break;',
'',
' case ' + op.POP + ':', // POP
' stack.pop();',
' ip++;',
' break;',
'',
' case ' + op.POP_CURR_POS + ':', // POP_CURR_POS
' peg$currPos = stack.pop();',
' ip++;',
' break;',
'',
' case ' + op.POP_N + ':', // POP_N n
' stack.length -= bc[ip + 1];',
' ip += 2;',
' break;',
'',
' case ' + op.NIP + ':', // NIP
' stack.splice(-2, 1);',
' ip++;',
' break;',
'',
' case ' + op.APPEND + ':', // APPEND
' stack[stack.length - 2].push(stack.pop());',
' ip++;',
' break;',
'',
' case ' + op.WRAP + ':', // WRAP n
' stack.push(stack.splice(stack.length - bc[ip + 1], bc[ip + 1]));',
' ip += 2;',
' break;',
'',
' case ' + op.TEXT + ':', // TEXT
' stack.push(input.substring(stack.pop(), peg$currPos));',
' ip++;',
' break;',
'',
' case ' + op.IF + ':', // IF t, f
indent10(generateCondition('stack[stack.length - 1]', 0)),
'',
' case ' + op.IF_ERROR + ':', // IF_ERROR t, f
indent10(generateCondition(
'stack[stack.length - 1] === peg$FAILED',
0
)),
'',
' case ' + op.IF_NOT_ERROR + ':', // IF_NOT_ERROR t, f
indent10(
generateCondition('stack[stack.length - 1] !== peg$FAILED',
0
)),
'',
' case ' + op.WHILE_NOT_ERROR + ':', // WHILE_NOT_ERROR b
indent10(generateLoop('stack[stack.length - 1] !== peg$FAILED')),
'',
' case ' + op.MATCH_ANY + ':', // MATCH_ANY a, f, ...
indent10(generateCondition('input.length > peg$currPos', 0)),
'',
' case ' + op.MATCH_STRING + ':', // MATCH_STRING s, a, f, ...
indent10(generateCondition(
'input.substr(peg$currPos, peg$consts[bc[ip + 1]].length) === peg$consts[bc[ip + 1]]',
1
)),
'',
' case ' + op.MATCH_STRING_IC + ':', // MATCH_STRING_IC s, a, f, ...
indent10(generateCondition(
'input.substr(peg$currPos, peg$consts[bc[ip + 1]].length).toLowerCase() === peg$consts[bc[ip + 1]]',
1
)),
'',
' case ' + op.MATCH_REGEXP + ':', // MATCH_REGEXP r, a, f, ...
indent10(generateCondition(
'peg$consts[bc[ip + 1]].test(input.charAt(peg$currPos))',
1
)),
'',
' case ' + op.ACCEPT_N + ':', // ACCEPT_N n
' stack.push(input.substr(peg$currPos, bc[ip + 1]));',
' peg$currPos += bc[ip + 1];',
' ip += 2;',
' break;',
'',
' case ' + op.ACCEPT_STRING + ':', // ACCEPT_STRING s
' stack.push(peg$consts[bc[ip + 1]]);',
' peg$currPos += peg$consts[bc[ip + 1]].length;',
' ip += 2;',
' break;',
'',
' case ' + op.FAIL + ':', // FAIL e
' stack.push(peg$FAILED);',
' if (peg$silentFails === 0) {',
' peg$fail(peg$consts[bc[ip + 1]]);',
' }',
' ip += 2;',
' break;',
'',
' case ' + op.LOAD_SAVED_POS + ':', // LOAD_SAVED_POS p
' peg$savedPos = stack[stack.length - 1 - bc[ip + 1]];',
' ip += 2;',
' break;',
'',
' case ' + op.UPDATE_SAVED_POS + ':', // UPDATE_SAVED_POS
' peg$savedPos = peg$currPos;',
' ip++;',
' break;',
'',
' case ' + op.CALL + ':', // CALL f, n, pc, p1, p2, ..., pN
indent10(generateCall()),
'',
' case ' + op.RULE + ':', // RULE r
' stack.push(peg$parseRule(bc[ip + 1]));',
' ip += 2;',
' break;',
'',
' case ' + op.SILENT_FAILS_ON + ':', // SILENT_FAILS_ON
' peg$silentFails++;',
' ip++;',
' break;',
'',
' case ' + op.SILENT_FAILS_OFF + ':', // SILENT_FAILS_OFF
' peg$silentFails--;',
' ip++;',
' break;',
'',
' default:',
' throw new Error("Invalid opcode: " + bc[ip] + ".");',
' }',
' }',
'',
' if (ends.length > 0) {',
' end = ends.pop();',
' ip = ips.pop();',
' } else {',
' break;',
' }',
' }'
].join('\n'));
parts.push(indent2(generateRuleFooter('peg$ruleNames[index]', 'stack[0]')));
parts.push('}');
return parts.join('\n');
}
function generateRuleFunction(rule) {
var parts = [], code;
function c(i) { return "peg$c" + i; } // |consts[i]| of the abstract machine
function s(i) { return "s" + i; } // |stack[i]| of the abstract machine
var stack = {
sp: -1,
maxSp: -1,
push: function(exprCode) {
var code = s(++this.sp) + ' = ' + exprCode + ';';
if (this.sp > this.maxSp) { this.maxSp = this.sp; }
return code;
},
pop: function(n) {
var values;
if (n === void 0) {
return s(this.sp--);
} else {
values = arrays.map(arrays.range(this.sp - n + 1, this.sp + 1), s);
this.sp -= n;
return values;
}
},
top: function() {
return s(this.sp);
},
index: function(i) {
return s(this.sp - i);
}
};
function compile(bc) {
var ip = 0,
end = bc.length,
parts = [],
value;
function compileCondition(cond, argCount) {
var baseLength = argCount + 3,
thenLength = bc[ip + baseLength - 2],
elseLength = bc[ip + baseLength - 1],
baseSp = stack.sp,
thenCode, elseCode, thenSp, elseSp;
ip += baseLength;
thenCode = compile(bc.slice(ip, ip + thenLength));
thenSp = stack.sp;
ip += thenLength;
if (elseLength > 0) {
stack.sp = baseSp;
elseCode = compile(bc.slice(ip, ip + elseLength));
elseSp = stack.sp;
ip += elseLength;
if (thenSp !== elseSp) {
throw new Error(
"Branches of a condition must move the stack pointer in the same way."
);
}
}
parts.push('if (' + cond + ') {');
parts.push(indent2(thenCode));
if (elseLength > 0) {
parts.push('} else {');
parts.push(indent2(elseCode));
}
parts.push('}');
}
function compileLoop(cond) {
var baseLength = 2,
bodyLength = bc[ip + baseLength - 1],
baseSp = stack.sp,
bodyCode, bodySp;
ip += baseLength;
bodyCode = compile(bc.slice(ip, ip + bodyLength));
bodySp = stack.sp;
ip += bodyLength;
if (bodySp !== baseSp) {
throw new Error("Body of a loop can't move the stack pointer.");
}
parts.push('while (' + cond + ') {');
parts.push(indent2(bodyCode));
parts.push('}');
}
function compileCall() {
var baseLength = 4,
paramsLength = bc[ip + baseLength - 1];
var value = c(bc[ip + 1]) + '('
+ arrays.map(
bc.slice(ip + baseLength, ip + baseLength + paramsLength),
function(p) { return stack.index(p); }
).join(', ')
+ ')';
stack.pop(bc[ip + 2]);
parts.push(stack.push(value));
ip += baseLength + paramsLength;
}
while (ip < end) {
switch (bc[ip]) {
case op.PUSH: // PUSH c
parts.push(stack.push(c(bc[ip + 1])));
ip += 2;
break;
case op.PUSH_CURR_POS: // PUSH_CURR_POS
parts.push(stack.push('peg$currPos'));
ip++;
break;
case op.PUSH_UNDEFINED: // PUSH_UNDEFINED
parts.push(stack.push('void 0'));
ip++;
break;
case op.PUSH_NULL: // PUSH_NULL
parts.push(stack.push('null'));
ip++;
break;
case op.PUSH_FAILED: // PUSH_FAILED
parts.push(stack.push('peg$FAILED'));
ip++;
break;
case op.PUSH_EMPTY_ARRAY: // PUSH_EMPTY_ARRAY
parts.push(stack.push('[]'));
ip++;
break;
case op.POP: // POP
stack.pop();
ip++;
break;
case op.POP_CURR_POS: // POP_CURR_POS
parts.push('peg$currPos = ' + stack.pop() + ';');
ip++;
break;
case op.POP_N: // POP_N n
stack.pop(bc[ip + 1]);
ip += 2;
break;
case op.NIP: // NIP
value = stack.pop();
stack.pop();
parts.push(stack.push(value));
ip++;
break;
case op.APPEND: // APPEND
value = stack.pop();
parts.push(stack.top() + '.push(' + value + ');');
ip++;
break;
case op.WRAP: // WRAP n
parts.push(
stack.push('[' + stack.pop(bc[ip + 1]).join(', ') + ']')
);
ip += 2;
break;
case op.TEXT: // TEXT
parts.push(
stack.push('input.substring(' + stack.pop() + ', peg$currPos)')
);
ip++;
break;
case op.IF: // IF t, f
compileCondition(stack.top(), 0);
break;
case op.IF_ERROR: // IF_ERROR t, f
compileCondition(stack.top() + ' === peg$FAILED', 0);
break;
case op.IF_NOT_ERROR: // IF_NOT_ERROR t, f
compileCondition(stack.top() + ' !== peg$FAILED', 0);
break;
case op.WHILE_NOT_ERROR: // WHILE_NOT_ERROR b
compileLoop(stack.top() + ' !== peg$FAILED', 0);
break;
case op.MATCH_ANY: // MATCH_ANY a, f, ...
compileCondition('input.length > peg$currPos', 0);
break;
case op.MATCH_STRING: // MATCH_STRING s, a, f, ...
compileCondition(
eval(ast.consts[bc[ip + 1]]).length > 1
? 'input.substr(peg$currPos, '
+ eval(ast.consts[bc[ip + 1]]).length
+ ') === '
+ c(bc[ip + 1])
: 'input.charCodeAt(peg$currPos) === '
+ eval(ast.consts[bc[ip + 1]]).charCodeAt(0),
1
);
break;
case op.MATCH_STRING_IC: // MATCH_STRING_IC s, a, f, ...
compileCondition(
'input.substr(peg$currPos, '
+ eval(ast.consts[bc[ip + 1]]).length
+ ').toLowerCase() === '
+ c(bc[ip + 1]),
1
);
break;
case op.MATCH_REGEXP: // MATCH_REGEXP r, a, f, ...
compileCondition(
c(bc[ip + 1]) + '.test(input.charAt(peg$currPos))',
1
);
break;
case op.ACCEPT_N: // ACCEPT_N n
parts.push(stack.push(
bc[ip + 1] > 1
? 'input.substr(peg$currPos, ' + bc[ip + 1] + ')'
: 'input.charAt(peg$currPos)'
));
parts.push(
bc[ip + 1] > 1
? 'peg$currPos += ' + bc[ip + 1] + ';'
: 'peg$currPos++;'
);
ip += 2;
break;
case op.ACCEPT_STRING: // ACCEPT_STRING s
parts.push(stack.push(c(bc[ip + 1])));
parts.push(
eval(ast.consts[bc[ip + 1]]).length > 1
? 'peg$currPos += ' + eval(ast.consts[bc[ip + 1]]).length + ';'
: 'peg$currPos++;'
);
ip += 2;
break;
case op.FAIL: // FAIL e
parts.push(stack.push('peg$FAILED'));
parts.push('if (peg$silentFails === 0) { peg$fail(' + c(bc[ip + 1]) + '); }');
ip += 2;
break;
case op.LOAD_SAVED_POS: // LOAD_SAVED_POS p
parts.push('peg$savedPos = ' + stack.index(bc[ip + 1]) + ';');
ip += 2;
break;
case op.UPDATE_SAVED_POS: // UPDATE_SAVED_POS
parts.push('peg$savedPos = peg$currPos;');
ip++;
break;
case op.CALL: // CALL f, n, pc, p1, p2, ..., pN
compileCall();
break;
case op.RULE: // RULE r
parts.push(stack.push("peg$parse" + ast.rules[bc[ip + 1]].name + "()"));
ip += 2;
break;
case op.SILENT_FAILS_ON: // SILENT_FAILS_ON
parts.push('peg$silentFails++;');
ip++;
break;
case op.SILENT_FAILS_OFF: // SILENT_FAILS_OFF
parts.push('peg$silentFails--;');
ip++;
break;
default:
throw new Error("Invalid opcode: " + bc[ip] + ".");
}
}
return parts.join('\n');
}
code = compile(rule.bytecode);
parts.push('function peg$parse' + rule.name + '() {');
if (options.trace) {
parts.push([
' var ' + arrays.map(arrays.range(0, stack.maxSp + 1), s).join(', ') + ',',
' startPos = peg$currPos;'
].join('\n'));
} else {
parts.push(
' var ' + arrays.map(arrays.range(0, stack.maxSp + 1), s).join(', ') + ';'
);
}
parts.push(indent2(generateRuleHeader(
'"' + js.stringEscape(rule.name) + '"',
asts.indexOfRule(ast, rule.name)
)));
parts.push(indent2(code));
parts.push(indent2(generateRuleFooter(
'"' + js.stringEscape(rule.name) + '"',
s(0)
)));
parts.push('}');
return parts.join('\n');
}
function generateToplevel() {
var parts = [],
startRuleIndices, startRuleIndex,
startRuleFunctions, startRuleFunction,
ruleNames;
parts.push([
'function peg$subclass(child, parent) {',
' function ctor() { this.constructor = child; }',
' ctor.prototype = parent.prototype;',
' child.prototype = new ctor();',
'}',
'',
'function peg$SyntaxError(message, expected, found, location) {',
' this.message = message;',
' this.expected = expected;',
' this.found = found;',
' this.location = location;',
' this.name = "SyntaxError";',
'',
' if (typeof Error.captureStackTrace === "function") {',
' Error.captureStackTrace(this, peg$SyntaxError);',
' }',
'}',
'',
'peg$subclass(peg$SyntaxError, Error);',
'',
'peg$SyntaxError.buildMessage = function(expected, found) {',
' var DESCRIBE_EXPECTATION_FNS = {',
' literal: function(expectation) {',
' return "\\\"" + literalEscape(expectation.text) + "\\\"";',
' },',
'',
' class: function(expectation) {',
' var escapedParts = "",',
' i;',
'',
' for (i = 0; i < expectation.parts.length; i++) {',
' escapedParts += expectation.parts[i] instanceof Array',
' ? classEscape(expectation.parts[i][0]) + "-" + classEscape(expectation.parts[i][1])',
' : classEscape(expectation.parts[i]);',
' }',
'',
' return "[" + (expectation.inverted ? "^" : "") + escapedParts + "]";',
' },',
'',
' any: function(expectation) {',
' return "any character";',
' },',
'',
' end: function(expectation) {',
' return "end of input";',
' },',
'',
' other: function(expectation) {',
' return expectation.description;',
' }',
' };',
'',
' function hex(ch) {',
' return ch.charCodeAt(0).toString(16).toUpperCase();',
' }',
'',
' function literalEscape(s) {',
' return s',
' .replace(/\\\\/g, \'\\\\\\\\\')', // backslash
' .replace(/"/g, \'\\\\"\')', // closing double quote
' .replace(/\\0/g, \'\\\\0\')', // null
' .replace(/\\t/g, \'\\\\t\')', // horizontal tab
' .replace(/\\n/g, \'\\\\n\')', // line feed
' .replace(/\\r/g, \'\\\\r\')', // carriage return
' .replace(/[\\x00-\\x0F]/g, function(ch) { return \'\\\\x0\' + hex(ch); })',
' .replace(/[\\x10-\\x1F\\x7F-\\x9F]/g, function(ch) { return \'\\\\x\' + hex(ch); });',
' }',
'',
' function classEscape(s) {',
' return s',
' .replace(/\\\\/g, \'\\\\\\\\\')', // backslash
' .replace(/\\]/g, \'\\\\]\')', // closing bracket
' .replace(/\\^/g, \'\\\\^\')', // caret
' .replace(/-/g, \'\\\\-\')', // dash
' .replace(/\\0/g, \'\\\\0\')', // null
' .replace(/\\t/g, \'\\\\t\')', // horizontal tab
' .replace(/\\n/g, \'\\\\n\')', // line feed
' .replace(/\\r/g, \'\\\\r\')', // carriage return
' .replace(/[\\x00-\\x0F]/g, function(ch) { return \'\\\\x0\' + hex(ch); })',
' .replace(/[\\x10-\\x1F\\x7F-\\x9F]/g, function(ch) { return \'\\\\x\' + hex(ch); });',
' }',
'',
' function describeExpectation(expectation) {',
' return DESCRIBE_EXPECTATION_FNS[expectation.type](expectation);',
' }',
'',
' function describeExpected(expected) {',
' var descriptions = new Array(expected.length),',
' i, j;',
'',
' for (i = 0; i < expected.length; i++) {',
' descriptions[i] = describeExpectation(expected[i]);',
' }',
'',
' descriptions.sort();',
'',
' if (descriptions.length > 0) {',
' for (i = 1, j = 1; i < descriptions.length; i++) {',
' if (descriptions[i - 1] !== descriptions[i]) {',
' descriptions[j] = descriptions[i];',
' j++;',
' }',
' }',
' descriptions.length = j;',
' }',
'',
' return descriptions.length > 1',
' ? descriptions.slice(0, -1).join(", ")',
' + " or "',
' + descriptions[descriptions.length - 1]',
' : descriptions[0];',
' }',
'',
' function describeFound(found) {',
' return found ? "\\"" + literalEscape(found) + "\\"" : "end of input";',
' }',
'',
' return "Expected " + describeExpected(expected) + " but " + describeFound(found) + " found.";',
'};',
''
].join('\n'));
if (options.trace) {
parts.push([
'function peg$DefaultTracer() {',
' this.indentLevel = 0;',
'}',
'',
'peg$DefaultTracer.prototype.trace = function(event) {',
' var that = this;',
'',
' function log(event) {',
' function repeat(string, n) {',
' var result = "", i;',
'',
' for (i = 0; i < n; i++) {',
' result += string;',
' }',
'',
' return result;',
' }',
'',
' function pad(string, length) {',
' return string + repeat(" ", length - string.length);',
' }',
'',
' if (typeof console === "object") {', // IE 8-10
' console.log(',
' event.location.start.line + ":" + event.location.start.column + "-"',
' + event.location.end.line + ":" + event.location.end.column + " "',
' + pad(event.type, 10) + " "',
' + repeat(" ", that.indentLevel) + event.rule',
' );',
' }',
' }',
'',
' switch (event.type) {',
' case "rule.enter":',
' log(event);',
' this.indentLevel++;',
' break;',
'',
' case "rule.match":',
' this.indentLevel--;',
' log(event);',
' break;',
'',
' case "rule.fail":',
' this.indentLevel--;',
' log(event);',
' break;',
'',
' default:',
' throw new Error("Invalid event type: " + event.type + ".");',
' }',
'};',
''
].join('\n'));
}
parts.push([
'function peg$parse(input, options) {',
' options = options !== void 0 ? options : {};',
'',
' var parser = this,',
'',
' peg$FAILED = {},',
''
].join('\n'));
if (options.optimize === "size") {
startRuleIndices = '{ '
+ arrays.map(
options.allowedStartRules,
function(r) { return r + ': ' + asts.indexOfRule(ast, r); }
).join(', ')
+ ' }';
startRuleIndex = asts.indexOfRule(ast, options.allowedStartRules[0]);
parts.push([
' peg$startRuleIndices = ' + startRuleIndices + ',',
' peg$startRuleIndex = ' + startRuleIndex + ','
].join('\n'));
} else {
startRuleFunctions = '{ '
+ arrays.map(
options.allowedStartRules,
function(r) { return r + ': peg$parse' + r; }
).join(', ')
+ ' }';
startRuleFunction = 'peg$parse' + options.allowedStartRules[0];
parts.push([
' peg$startRuleFunctions = ' + startRuleFunctions + ',',
' peg$startRuleFunction = ' + startRuleFunction + ','
].join('\n'));
}
parts.push('');
parts.push(indent6(generateTables()));
parts.push([
'',
' peg$currPos = 0,',
' peg$savedPos = 0,',
' peg$posDetailsCache = [{ line: 1, column: 1 }],',
' peg$maxFailPos = 0,',
' peg$maxFailExpected = [],',
' peg$silentFails = 0,', // 0 = report failures, > 0 = silence failures
''
].join('\n'));
if (options.cache) {
parts.push([
' peg$resultsCache = {},',
''
].join('\n'));
}
if (options.trace) {
if (options.optimize === "size") {
ruleNames = '['
+ arrays.map(
ast.rules,
function(r) { return '"' + js.stringEscape(r.name) + '"'; }
).join(', ')
+ ']';
parts.push([
' peg$ruleNames = ' + ruleNames + ',',
''
].join('\n'));
}
parts.push([
' peg$tracer = "tracer" in options ? options.tracer : new peg$DefaultTracer(),',
''
].join('\n'));
}
parts.push([
' peg$result;',
''
].join('\n'));
if (options.optimize === "size") {
parts.push([
' if ("startRule" in options) {',
' if (!(options.startRule in peg$startRuleIndices)) {',
' throw new Error("Can\'t start parsing from rule \\"" + options.startRule + "\\".");',
' }',
'',
' peg$startRuleIndex = peg$startRuleIndices[options.startRule];',
' }'
].join('\n'));
} else {
parts.push([
' if ("startRule" in options) {',
' if (!(options.startRule in peg$startRuleFunctions)) {',
' throw new Error("Can\'t start parsing from rule \\"" + options.startRule + "\\".");',
' }',
'',
' peg$startRuleFunction = peg$startRuleFunctions[options.startRule];',
' }'
].join('\n'));
}
parts.push([
'',
' function text() {',
' return input.substring(peg$savedPos, peg$currPos);',
' }',
'',
' function location() {',
' return peg$computeLocation(peg$savedPos, peg$currPos);',
' }',
'',
' function expected(description, location) {',
' location = location !== void 0 ? location : peg$computeLocation(peg$savedPos, peg$currPos)',
'',
' throw peg$buildException(',
' null,',
' [peg$otherExpectation(description)],',
' input.substring(peg$savedPos, peg$currPos),',
' location',
' );',
' }',
'',
' function error(message, location) {',
' location = location !== void 0 ? location : peg$computeLocation(peg$savedPos, peg$currPos)',
'',
' throw peg$buildException(',
' message,',
' null,',
' input.substring(peg$savedPos, peg$currPos),',
' location',
' );',
' }',
'',
' function peg$literalExpectation(text, ignoreCase) {',
' return { type: "literal", text: text, ignoreCase: ignoreCase };',
' }',
'',
' function peg$classExpectation(parts, inverted, ignoreCase) {',
' return { type: "class", parts: parts, inverted: inverted, ignoreCase: ignoreCase };',
' }',
'',
' function peg$anyExpectation() {',
' return { type: "any" };',
' }',
'',
' function peg$endExpectation() {',
' return { type: "end" };',
' }',
'',
' function peg$otherExpectation(description) {',
' return { type: "other", description: description };',
' }',
'',
' function peg$computePosDetails(pos) {',
' var details = peg$posDetailsCache[pos], p;',
'',
' if (details) {',
' return details;',
' } else {',
' p = pos - 1;',
' while (!peg$posDetailsCache[p]) {',
' p--;',
' }',
'',
' details = peg$posDetailsCache[p];',
' details = {',
' line: details.line,',
' column: details.column',
' };',
'',
' while (p < pos) {',
' if (input.charCodeAt(p) === 10) {',
' details.line++;',
' details.column = 1;',
' } else {',
' details.column++;',
' }',
'',
' p++;',
' }',
'',
' peg$posDetailsCache[pos] = details;',
' return details;',
' }',
' }',
'',
' function peg$computeLocation(startPos, endPos) {',
' var startPosDetails = peg$computePosDetails(startPos),',
' endPosDetails = peg$computePosDetails(endPos);',
'',
' return {',
' start: {',
' offset: startPos,',
' line: startPosDetails.line,',
' column: startPosDetails.column',
' },',
' end: {',
' offset: endPos,',
' line: endPosDetails.line,',
' column: endPosDetails.column',
' }',
' };',
' }',
'',
' function peg$fail(expected) {',
' if (peg$currPos < peg$maxFailPos) { return; }',
'',
' if (peg$currPos > peg$maxFailPos) {',
' peg$maxFailPos = peg$currPos;',
' peg$maxFailExpected = [];',
' }',
'',
' peg$maxFailExpected.push(expected);',
' }',
'',
' function peg$buildException(message, expected, found, location) {',
' return new peg$SyntaxError(',
' message !== null ? message : peg$SyntaxError.buildMessage(expected, found),',
' expected,',
' found,',
' location',
' );',
' }',
''
].join('\n'));
if (options.optimize === "size") {
parts.push(indent2(generateInterpreter()));
parts.push('');
} else {
arrays.each(ast.rules, function(rule) {
parts.push(indent2(generateRuleFunction(rule)));
parts.push('');
});
}
if (ast.initializer) {
parts.push(indent2(ast.initializer.code));
parts.push('');
}
if (options.optimize === "size") {
parts.push(' peg$result = peg$parseRule(peg$startRuleIndex);');
} else {
parts.push(' peg$result = peg$startRuleFunction();');
}
parts.push([
'',
' if (peg$result !== peg$FAILED && peg$currPos === input.length) {',
' return peg$result;',
' } else {',
' if (peg$result !== peg$FAILED && peg$currPos < input.length) {',
' peg$fail(peg$endExpectation());',
' }',
'',
' throw peg$buildException(',
' null,',
' peg$maxFailExpected,',
' peg$maxFailPos < input.length ? input.charAt(peg$maxFailPos) : null,',
' peg$maxFailPos < input.length',
' ? peg$computeLocation(peg$maxFailPos, peg$maxFailPos + 1)',
' : peg$computeLocation(peg$maxFailPos, peg$maxFailPos)',
' );',
' }',
'}'
].join('\n'));
return parts.join('\n');
}
function generateWrapper(toplevelCode) {
function generateGeneratedByComment() {
return [
'/*',
' * Generated by PEG.js 0.9.0.',
' *',
' * http://pegjs.org/',
' */'
].join('\n');
}
function generateParserObject() {
return options.trace
? [
'{',
' SyntaxError: peg$SyntaxError,',
' DefaultTracer: peg$DefaultTracer,',
' parse: peg$parse',
'}'
].join('\n')
: [
'{',
' SyntaxError: peg$SyntaxError,',
' parse: peg$parse',
'}'
].join('\n');
}
var generators = {
bare: function() {
return [
generateGeneratedByComment(),
'(function() {',
' "use strict";',
'',
indent2(toplevelCode),
'',
indent2('return ' + generateParserObject() + ';'),
'})()'
].join('\n');
},
umd: function() {
var parts = [],
dependencyIds = objects.values(options.dependencies),
dependencyVars = objects.keys(options.dependencies),
dependencies = '['
+ arrays.map(
dependencyIds,
function(id) { return '"' + js.stringEscape(id) + '"'; }
).join(', ')
+ ']',
requires = arrays.map(
dependencyIds,
function(id) { return 'require("' + js.stringEscape(id) + '")'; }
).join(', '),
params = dependencyVars.join(', ');
parts.push([
generateGeneratedByComment(),
'(function(root, factory) {',
' if (typeof define === "function" && define.amd) {',
' define(' + dependencies + ', factory);',
' } else if (typeof module === "object" && module.exports) {',
' module.exports = factory(' + requires + ');'
].join('\n'));
if (options.exportVar !== null) {
parts.push([
' } else {',
' root.' + options.exportVar + ' = factory();'
].join('\n'));
}
parts.push([
' }',
'})(this, function(' + params + ') {',
' "use strict";',
'',
indent2(toplevelCode),
'',
indent2('return ' + generateParserObject() + ';'),
'});',
''
].join('\n'));
return parts.join('\n');
}
};
return generators[options.format]();
}
ast.code = generateWrapper(generateToplevel());
}
module.exports = generateJS;