Trying to parse JS file with return statement: 'return' outside of function #288
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Please fix this. Returning at the global scope is allowed. |
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@stephenmathieson: Not according to ES5 it's not. Some interpreters like node wrap your program in a function, changing its behaviour. See nodejs/node-v0.x-archive#6254 |
<!doctype html>
<script>return;</script>
<script>alert("it works");</script> |
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Yes, I said that. It's still not valid JavaScript. |
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It could be nice with an option to allow global scope returns. |
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I'm trying to uglify a commonJS module in which it is perfectly valid to return from, but I cannot get past this error. |
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I'll bite. Who/what told you it was valid? |
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CommonJS modules are wrapped in functions. The following example is valid and works fine: We use return from within modules in many many places. The issue is that uglify assumes that the contents of a JS file are going to be in global scope, but dynamically loaded modules are not in the global scope. |
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This is the CommonJS spec: http://wiki.commonjs.org/wiki/Modules/1.1 Where does it say "CommonJS modules are wrapped in functions"? It says "These modules are offered privacy of their top scope", which some implementations (node) choose to implement as a function body. This also gives them a convenient way to introduce the CommonJS module context. But it unintentionally (and incorrectly) adds support for top-level return. Don't take advantage of this feature. |
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That has nothing to do with uglify. But fair enough mine was a bad example, so forget commonJS and consider a situation where one is building a massive JS-based application with hundreds of Javascript files in pieces that get concatenated together and wrapped in functions (or not) depending on a complex build script. Why should I not be able to uglify my individual files before putting them together, so that I know what has been uglified and what goes where? Scope needn't be relevant to uglify. "Don't take advantage of this feature." So will uglify also tell me that I am not allowed to use eval or non-strict equals? |
No way. :-) In any case, the idea is that the parser tries to be spec-compliant, and by the JS spec the |
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Oh I certainly wasn't suggesting for a moment that ignoring return outside function should be standard behavior, clearly that would be inappropriate for most situations (even more now that I have been enlightened about the CJS spec). This is clearly a specialist case but it seems at least a couple of people want it for one reason or another. Awesomes. |
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There you go. Pass |
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thanks!! |
I'm trying to parse a JS file that looks a bit like this:
However, I get an error:
'return' outside of function [test.js:1,29]What I want to do is parse the above JS file and then run my custom TreeTransformer. Can I tell the parser to ignore this error, as I'm already fixing it by wrapping it in a lambda function afterwards (and then doing some more transformations).
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