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pohatu/FizzBuzz.PEG.js

Last active August 29, 2015 14:00
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FizzBuss.PEG.js
Raw
FizzBuzz.PEG.js
/*
* FizzBuzz as a PEG Parser
* This is the grammar to input to PEG.JS
* Output is a JS Parser that will recognize numbers and convert them to:
* "fizz" if multiples of 3, "buzz" if multiples of 5, and "fizzbuzz" if multiples of 3 and 5.
* Using predicates, I was able to get this to actually create fizz, buzz, and fizzbuzz tokens! Woo! Hoo!
*/
start
= elements:(e:element delims? { return e;})+ {return elements;}
element
= fizzbuzz / fizz / buzz / integer
delims
= [ \n\t,;]+ { return " "}
integer "integer"
= digits:[0-9]+ { return parseInt(digits.join(""), 10);;}
fizzbuzz "fizzbuzz"
= (i:integer &{if(i%15===0){return true;}}) { return "fizzbuzz";}
buzz "buzz"
= (i:integer &{if(i%5===0){return true;}}) { return "buzz";}
fizz "fizz"
= (i:integer &{if(i%3===0){return true;}}) { return "fizz";}
Raw
module.exports
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$c1 = peg$FAILED,
peg$c2 = null,
peg$c3 = function(e) { return e;},
peg$c4 = function(elements) {return elements;},
peg$c5 = /^[ \n\t,;]/,
peg$c6 = { type: "class", value: "[ \\n\\t,;]", description: "[ \\n\\t,;]" },
peg$c7 = function() { return " "},
peg$c8 = { type: "other", description: "integer" },
peg$c9 = /^[0-9]/,
peg$c10 = { type: "class", value: "[0-9]", description: "[0-9]" },
peg$c11 = function(digits) { return parseInt(digits.join(""), 10);;},
peg$c12 = { type: "other", description: "fizzbuzz" },
peg$c13 = function(i) {if(i%15===0){return true;}},
peg$c14 = void 0,
peg$c15 = function(i) { return "fizzbuzz";},
peg$c16 = { type: "other", description: "buzz" },
peg$c17 = function(i) {if(i%5===0){return true;}},
peg$c18 = function(i) { return "buzz";},
peg$c19 = { type: "other", description: "fizz" },
peg$c20 = function(i) {if(i%3===0){return true;}},
peg$c21 = function(i) { return "fizz";},
peg$currPos = 0,
peg$reportedPos = 0,
peg$cachedPos = 0,
peg$cachedPosDetails = { line: 1, column: 1, seenCR: false },
peg$maxFailPos = 0,
peg$maxFailExpected = [],
peg$silentFails = 0,
peg$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$parsestart() {
var s0, s1, s2, s3, s4;
s0 = peg$currPos;
s1 = [];
s2 = peg$currPos;
s3 = peg$parseelement();
if (s3 !== peg$FAILED) {
s4 = peg$parsedelims();
if (s4 === peg$FAILED) {
s4 = peg$c2;
}
if (s4 !== peg$FAILED) {
peg$reportedPos = s2;
s3 = peg$c3(s3);
s2 = s3;
} else {
peg$currPos = s2;
s2 = peg$c1;
}
} else {
peg$currPos = s2;
s2 = peg$c1;
}
if (s2 !== peg$FAILED) {
while (s2 !== peg$FAILED) {
s1.push(s2);
s2 = peg$currPos;
s3 = peg$parseelement();
if (s3 !== peg$FAILED) {
s4 = peg$parsedelims();
if (s4 === peg$FAILED) {
s4 = peg$c2;
}
if (s4 !== peg$FAILED) {
peg$reportedPos = s2;
s3 = peg$c3(s3);
s2 = s3;
} else {
peg$currPos = s2;
s2 = peg$c1;
}
} else {
peg$currPos = s2;
s2 = peg$c1;
}
}
} else {
s1 = peg$c1;
}
if (s1 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c4(s1);
}
s0 = s1;
return s0;
}
function peg$parseelement() {
var s0;
s0 = peg$parsefizzbuzz();
if (s0 === peg$FAILED) {
s0 = peg$parsefizz();
if (s0 === peg$FAILED) {
s0 = peg$parsebuzz();
if (s0 === peg$FAILED) {
s0 = peg$parseinteger();
}
}
}
return s0;
}
function peg$parsedelims() {
var s0, s1, s2;
s0 = peg$currPos;
s1 = [];
if (peg$c5.test(input.charAt(peg$currPos))) {
s2 = input.charAt(peg$currPos);
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c6); }
}
if (s2 !== peg$FAILED) {
while (s2 !== peg$FAILED) {
s1.push(s2);
if (peg$c5.test(input.charAt(peg$currPos))) {
s2 = input.charAt(peg$currPos);
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c6); }
}
}
} else {
s1 = peg$c1;
}
if (s1 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c7();
}
s0 = s1;
return s0;
}
function peg$parseinteger() {
var s0, s1, s2;
peg$silentFails++;
s0 = peg$currPos;
s1 = [];
if (peg$c9.test(input.charAt(peg$currPos))) {
s2 = input.charAt(peg$currPos);
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c10); }
}
if (s2 !== peg$FAILED) {
while (s2 !== peg$FAILED) {
s1.push(s2);
if (peg$c9.test(input.charAt(peg$currPos))) {
s2 = input.charAt(peg$currPos);
peg$currPos++;
} else {
s2 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c10); }
}
}
} else {
s1 = peg$c1;
}
if (s1 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c11(s1);
}
s0 = s1;
peg$silentFails--;
if (s0 === peg$FAILED) {
s1 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c8); }
}
return s0;
}
function peg$parsefizzbuzz() {
var s0, s1, s2;
peg$silentFails++;
s0 = peg$currPos;
s1 = peg$parseinteger();
if (s1 !== peg$FAILED) {
peg$reportedPos = peg$currPos;
s2 = peg$c13(s1);
if (s2) {
s2 = peg$c14;
} else {
s2 = peg$c1;
}
if (s2 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c15(s1);
s0 = s1;
} else {
peg$currPos = s0;
s0 = peg$c1;
}
} else {
peg$currPos = s0;
s0 = peg$c1;
}
peg$silentFails--;
if (s0 === peg$FAILED) {
s1 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c12); }
}
return s0;
}
function peg$parsebuzz() {
var s0, s1, s2;
peg$silentFails++;
s0 = peg$currPos;
s1 = peg$parseinteger();
if (s1 !== peg$FAILED) {
peg$reportedPos = peg$currPos;
s2 = peg$c17(s1);
if (s2) {
s2 = peg$c14;
} else {
s2 = peg$c1;
}
if (s2 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c18(s1);
s0 = s1;
} else {
peg$currPos = s0;
s0 = peg$c1;
}
} else {
peg$currPos = s0;
s0 = peg$c1;
}
peg$silentFails--;
if (s0 === peg$FAILED) {
s1 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c16); }
}
return s0;
}
function peg$parsefizz() {
var s0, s1, s2;
peg$silentFails++;
s0 = peg$currPos;
s1 = peg$parseinteger();
if (s1 !== peg$FAILED) {
peg$reportedPos = peg$currPos;
s2 = peg$c20(s1);
if (s2) {
s2 = peg$c14;
} else {
s2 = peg$c1;
}
if (s2 !== peg$FAILED) {
peg$reportedPos = s0;
s1 = peg$c21(s1);
s0 = s1;
} else {
peg$currPos = s0;
s0 = peg$c1;
}
} else {
peg$currPos = s0;
s0 = peg$c1;
}
peg$silentFails--;
if (s0 === peg$FAILED) {
s1 = peg$FAILED;
if (peg$silentFails === 0) { peg$fail(peg$c19); }
}
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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