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darbicus/peg.js

Created May 1, 2014 05:43
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PEMDAS parser made using pegjs
Raw
peg.js
module.exports = (function() {
/*
* Generated by PEG.js 0.8.0.
*
* http://pegjs.majda.cz/
*/
function peg$subclass(child, parent) {
function ctor() { this.constructor = child; }
ctor.prototype = parent.prototype;
child.prototype = new ctor();
}
function SyntaxError(message, expected, found, offset, line, column) {
this.message = message;
this.expected = expected;
this.found = found;
this.offset = offset;
this.line = line;
this.column = column;
this.name = "SyntaxError";
}
peg$subclass(SyntaxError, Error);
function parse(input) {
var options = arguments.length > 1 ? arguments[1] : {},
peg$FAILED = {},
peg$startRuleFunctions = { start: peg$parsestart },
peg$startRuleFunction = peg$parsestart,
peg$c0 = peg$FAILED,
peg$c1 = "+",
peg$c2 = { type: "literal", value: "+", description: "\"+\"" },
peg$c3 = function(left, right) { return left + right; },
peg$c4 = "-",
peg$c5 = { type: "literal", value: "-", description: "\"-\"" },
peg$c6 = function(left, right) { return left-right;},
peg$c7 = "*",
peg$c8 = { type: "literal", value: "*", description: "\"*\"" },
peg$c9 = function(left, right) { return left * right; },
peg$c10 = "(",
peg$c11 = { type: "literal", value: "(", description: "\"(\"" },
peg$c12 = ")",
peg$c13 = { type: "literal", value: ")", description: "\")\"" },
peg$c14 = function(left, inside) {return left*inside;},
peg$c15 = "/",
peg$c16 = { type: "literal", value: "/", description: "\"/\"" },
peg$c17 = function(left, right) { return left / right;},
peg$c18 = "^",
peg$c19 = { type: "literal", value: "^", description: "\"^\"" },
peg$c20 = function(left, right) { return Math.pow(left,right);},
peg$c21 = function(inside) { return inside; },
peg$c22 = { type: "other", description: "real" },
peg$c23 = [],
peg$c24 = /^[0-9.]/,
peg$c25 = { type: "class", value: "[0-9.]", description: "[0-9.]" },
peg$c26 = function(digits) { return parseFloat(digits.join("")); },
peg$c27 = function(right) {return parseFloat("-"+right);},
peg$currPos = 0,
peg$reportedPos = 0,
peg$cachedPos = 0,
peg$cachedPosDetails = { line: 1, column: 1, seenCR: false },
peg$maxFailPos = 0,
peg$maxFailExpected = [],
peg$silentFails = 0,
peg$cache = {},
peg$result;
if ("startRule" in options) {
if (!(options.startRule in peg$startRuleFunctions)) {
throw new Error("Can't start parsing from rule \"" + options.startRule + "\".");
}
peg$startRuleFunction = peg$startRuleFunctions[options.startRule];
}
function text() {
return input.substring(peg$reportedPos, peg$currPos);
}
function offset() {
return peg$reportedPos;
}
function line() {
return peg$computePosDetails(peg$reportedPos).line;
}
function column() {
return peg$computePosDetails(peg$reportedPos).column;
}
function expected(description) {
throw peg$buildException(
null,
[{ type: "other", description: description }],
peg$reportedPos
);
}
function error(message) {
throw peg$buildException(message, null, peg$reportedPos);
}
function peg$computePosDetails(pos) {
function advance(details, startPos, endPos) {
var p, ch;
for (p = startPos; p < endPos; p++) {
ch = input.charAt(p);
if (ch === "\n") {
if (!details.seenCR) { details.line++; }
details.column = 1;
details.seenCR = false;
} else if (ch === "\r" || ch === "\u2028" || ch === "\u2029") {
details.line++;
details.column = 1;
details.seenCR = true;
} else {
details.column++;
details.seenCR = false;
}
}
}
if (peg$cachedPos !== pos) {
if (peg$cachedPos > pos) {
peg$cachedPos = 0;
peg$cachedPosDetails = { line: 1, column: 1, seenCR: false };
}
advance(peg$cachedPosDetails, peg$cachedPos, pos);
peg$cachedPos = pos;
}
return peg$cachedPosDetails;
}
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, pos) {
function cleanupExpected(expected) {
var i = 1;
expected.sort(function(a, b) {
if (a.description < b.description) {
return -1;
} else if (a.description > b.description) {
return 1;
} else {
return 0;
}
});
while (i < expected.length) {
if (expected[i - 1] === expected[i]) {
expected.splice(i, 1);
} else {
i++;
}
}
}
function buildMessage(expected, found) {
function stringEscape(s) {
function hex(ch) { return ch.charCodeAt(0).toString(16).toUpperCase(); }
return s
.replace(/\\/g, '\\\\')
.replace(/"/g, '\\"')
.replace(/\x08/g, '\\b')
.replace(/\t/g, '\\t')
.replace(/\n/g, '\\n')
.replace(/\f/g, '\\f')
.replace(/\r/g, '\\r')
.replace(/[\x00-\x07\x0B\x0E\x0F]/g, function(ch) { return '\\x0' + hex(ch); })
.replace(/[\x10-\x1F\x80-\xFF]/g, function(ch) { return '\\x' + hex(ch); })
.replace(/[\u0180-\u0FFF]/g, function(ch) { return '\\u0' + hex(ch); })
.replace(/[\u1080-\uFFFF]/g, function(ch) { return '\\u' + hex(ch); });
}
var expectedDescs = new Array(expected.length),
expectedDesc, foundDesc, i;
for (i = 0; i < expected.length; i++) {
expectedDescs[i] = expected[i].description;
}
expectedDesc = expected.length > 1
? expectedDescs.slice(0, -1).join(", ")
+ " or "
+ expectedDescs[expected.length - 1]
: expectedDescs[0];
foundDesc = found ? "\"" + stringEscape(found) + "\"" : "end of input";
return "Expected " + expectedDesc + " but " + foundDesc + " found.";
}
var posDetails = peg$computePosDetails(pos),
found = pos < input.length ? input.charAt(pos) : null;
if (expected !== null) {
cleanupExpected(expected);
}
return new SyntaxError(
message !== null ? message : buildMessage(expected, found),
expected,
found,
pos,
posDetails.line,
posDetails.column
);
}
function peg$parsestart() {
var s0;
var key = peg$currPos * 10 + 0,
cached = peg$cache[key];
if (cached) {
peg$currPos = cached.nextPos;
return cached.result;
}
s0 = peg$parseadditive();
peg$cache[key] = { nextPos: peg$currPos, result: s0 };
return s0;
}
function peg$parseadditive() {
var s0, s1, s2, s3;
var key = peg$currPos * 10 + 1,
cached = peg$cache[key];
if (cached) {
peg$currPos = cached.nextPos;
return cached.result;
}
s0 = peg$currPos;
s1 = peg$parsemultiplicative();
if (s1 !== peg$FAILED) {
if (input.charCodeAt(peg$currPos) === 43) {
s2 = peg$c1;
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c2); }
}
if (s2 !== peg$FAILED) {
s3 = peg$parseadditive();
if (s3 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c3(s1, s3);
s0 = s1;
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
if (s0 === peg$FAILED) {
s0 = peg$parsesubtractive();
}
peg$cache[key] = { nextPos: peg$currPos, result: s0 };
return s0;
}
function peg$parsesubtractive() {
var s0, s1, s2, s3;
var key = peg$currPos * 10 + 2,
cached = peg$cache[key];
if (cached) {
peg$currPos = cached.nextPos;
return cached.result;
}
s0 = peg$currPos;
s1 = peg$parsemultiplicative();
if (s1 !== peg$FAILED) {
if (input.charCodeAt(peg$currPos) === 45) {
s2 = peg$c4;
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c5); }
}
if (s2 !== peg$FAILED) {
s3 = peg$parsesubtractive();
if (s3 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c6(s1, s3);
s0 = s1;
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
if (s0 === peg$FAILED) {
s0 = peg$parsemultiplicative();
}
peg$cache[key] = { nextPos: peg$currPos, result: s0 };
return s0;
}
function peg$parsemultiplicative() {
var s0, s1, s2, s3;
var key = peg$currPos * 10 + 3,
cached = peg$cache[key];
if (cached) {
peg$currPos = cached.nextPos;
return cached.result;
}
s0 = peg$currPos;
s1 = peg$parseexponent();
if (s1 !== peg$FAILED) {
if (input.charCodeAt(peg$currPos) === 42) {
s2 = peg$c7;
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c8); }
}
if (s2 !== peg$FAILED) {
s3 = peg$parsemultiplicative();
if (s3 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c9(s1, s3);
s0 = s1;
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
if (s0 === peg$FAILED) {
s0 = peg$parsem2();
}
peg$cache[key] = { nextPos: peg$currPos, result: s0 };
return s0;
}
function peg$parsem2() {
var s0, s1, s2, s3, s4;
var key = peg$currPos * 10 + 4,
cached = peg$cache[key];
if (cached) {
peg$currPos = cached.nextPos;
return cached.result;
}
s0 = peg$currPos;
s1 = peg$parseexponent();
if (s1 !== peg$FAILED) {
if (input.charCodeAt(peg$currPos) === 40) {
s2 = peg$c10;
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c11); }
}
if (s2 !== peg$FAILED) {
s3 = peg$parsem2();
if (s3 !== peg$FAILED) {
if (input.charCodeAt(peg$currPos) === 41) {
s4 = peg$c12;
peg$currPos++;
} else {
s4 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c13); }
}
if (s4 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c14(s1, s3);
s0 = s1;
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
if (s0 === peg$FAILED) {
s0 = peg$parsedivide();
}
peg$cache[key] = { nextPos: peg$currPos, result: s0 };
return s0;
}
function peg$parsedivide() {
var s0, s1, s2, s3;
var key = peg$currPos * 10 + 5,
cached = peg$cache[key];
if (cached) {
peg$currPos = cached.nextPos;
return cached.result;
}
s0 = peg$currPos;
s1 = peg$parseexponent();
if (s1 !== peg$FAILED) {
if (input.charCodeAt(peg$currPos) === 47) {
s2 = peg$c15;
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c16); }
}
if (s2 !== peg$FAILED) {
s3 = peg$parsedivide();
if (s3 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c17(s1, s3);
s0 = s1;
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
if (s0 === peg$FAILED) {
s0 = peg$parseexponent();
}
peg$cache[key] = { nextPos: peg$currPos, result: s0 };
return s0;
}
function peg$parseexponent() {
var s0, s1, s2, s3;
var key = peg$currPos * 10 + 6,
cached = peg$cache[key];
if (cached) {
peg$currPos = cached.nextPos;
return cached.result;
}
s0 = peg$currPos;
s1 = peg$parseprimary();
if (s1 !== peg$FAILED) {
if (input.charCodeAt(peg$currPos) === 94) {
s2 = peg$c18;
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c19); }
}
if (s2 !== peg$FAILED) {
s3 = peg$parseexponent();
if (s3 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c20(s1, s3);
s0 = s1;
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
if (s0 === peg$FAILED) {
s0 = peg$parseprimary();
}
peg$cache[key] = { nextPos: peg$currPos, result: s0 };
return s0;
}
function peg$parseprimary() {
var s0, s1, s2, s3;
var key = peg$currPos * 10 + 7,
cached = peg$cache[key];
if (cached) {
peg$currPos = cached.nextPos;
return cached.result;
}
s0 = peg$parsereal();
if (s0 === peg$FAILED) {
s0 = peg$currPos;
if (input.charCodeAt(peg$currPos) === 40) {
s1 = peg$c10;
peg$currPos++;
} else {
s1 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c11); }
}
if (s1 !== peg$FAILED) {
s2 = peg$parseadditive();
if (s2 !== peg$FAILED) {
if (input.charCodeAt(peg$currPos) === 41) {
s3 = peg$c12;
peg$currPos++;
} else {
s3 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c13); }
}
if (s3 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c21(s2);
s0 = s1;
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
}
peg$cache[key] = { nextPos: peg$currPos, result: s0 };
return s0;
}
function peg$parsereal() {
var s0, s1, s2;
var key = peg$currPos * 10 + 8,
cached = peg$cache[key];
if (cached) {
peg$currPos = cached.nextPos;
return cached.result;
}
peg$silentFails++;
s0 = peg$currPos;
s1 = [];
if (peg$c24.test(input.charAt(peg$currPos))) {
s2 = input.charAt(peg$currPos);
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c25); }
}
if (s2 !== peg$FAILED) {
while (s2 !== peg$FAILED) {
s1.push(s2);
if (peg$c24.test(input.charAt(peg$currPos))) {
s2 = input.charAt(peg$currPos);
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c25); }
}
}
} else {
s1 = peg$c0;
}
if (s1 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c26(s1);
}
s0 = s1;
if (s0 === peg$FAILED) {
s0 = peg$parsenegative();
}
peg$silentFails--;
if (s0 === peg$FAILED) {
s1 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c22); }
}
peg$cache[key] = { nextPos: peg$currPos, result: s0 };
return s0;
}
function peg$parsenegative() {
var s0, s1, s2;
var key = peg$currPos * 10 + 9,
cached = peg$cache[key];
if (cached) {
peg$currPos = cached.nextPos;
return cached.result;
}
s0 = peg$currPos;
if (input.charCodeAt(peg$currPos) === 45) {
s1 = peg$c4;
peg$currPos++;
} else {
s1 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c5); }
}
if (s1 !== peg$FAILED) {
s2 = peg$parsereal();
if (s2 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c27(s2);
s0 = s1;
} else {
peg$currPos = s0;
s0 = peg$c0;
}
} else {
peg$currPos = s0;
s0 = peg$c0;
}
peg$cache[key] = { nextPos: peg$currPos, result: s0 };
return s0;
}
peg$result = peg$startRuleFunction();
if (peg$result !== peg$FAILED && peg$currPos === input.length) {
return peg$result;
} else {
if (peg$result !== peg$FAILED && peg$currPos < input.length) {
peg$fail({ type: "end", description: "end of input" });
}
throw peg$buildException(null, peg$maxFailExpected, peg$maxFailPos);
}
}
return {
SyntaxError: SyntaxError,
parse: parse
};
})();
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