joepie91/pegjs
1
0
Fork 0
Code Issues Pull requests Releases Wiki Activity

Found a neater trick how to defend against |undefined| redefinition

Browse source
This commit is contained in:
David Majda 2010-07-24 16:35:06 +02:00
parent c3b5c2131a
commit 98da358ef4
1 changed files with 5 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
lib/compiler.js
View file

@ -1,6 +1,6 @@
/* PEG.js compiler. */ /* PEG.js compiler. */
(function() { (function(undefined) {
/* ===== PEG ===== */ /* ===== PEG ===== */
@ -39,7 +39,7 @@ PEG.GrammarError.prototype = Error.prototype;
PEG.ArrayUtils = { PEG.ArrayUtils = {
/* Like Python's |range|, but without |step|. */ /* Like Python's |range|, but without |step|. */
range: function(start, stop) { range: function(start, stop) {
if (typeof(stop) === "undefined") { if (stop === undefined) {
stop = start; stop = start;
start = 0; start = 0;
} }
@ -193,11 +193,11 @@ PEG.Compiler = {
/\$\{([a-zA-Z_][a-zA-Z0-9_]*)(\|([a-zA-Z_][a-zA-Z0-9_]*))?\}/g, /\$\{([a-zA-Z_][a-zA-Z0-9_]*)(\|([a-zA-Z_][a-zA-Z0-9_]*))?\}/g,
function(match, name, dummy, filter) { function(match, name, dummy, filter) {
var value = vars[name]; var value = vars[name];
if (typeof(value) === "undefined") { if (value === undefined) {
throw new Error("Undefined variable: \"" + name + "\"."); throw new Error("Undefined variable: \"" + name + "\".");
} }
if (typeof(filter) !== "undefined" && filter != "") { // JavaScript engines differ here. if (filter !== undefined && filter != "") { // JavaScript engines differ here.
if (filter === "string") { if (filter === "string") {
return PEG.StringUtils.quote(value); return PEG.StringUtils.quote(value);
} else { } else {
@ -297,7 +297,7 @@ PEG.Compiler = {
rule_ref: rule_ref:
function(node) { function(node) {
if (typeof(ast.rules[node.name]) === "undefined") { if (ast.rules[node.name] === undefined) {
throw new PEG.GrammarError( throw new PEG.GrammarError(
"Referenced rule \"" + node.name + "\" does not exist." "Referenced rule \"" + node.name + "\" does not exist."
); );