116 lines
2.2 KiB
Markdown
116 lines
2.2 KiB
Markdown
---
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title: Free Code Camp JavaScript Style Guide
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---
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<small>or How Cool People Write JavaScript.</small>
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## Indent
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Always Use Two Spaces
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No hard tabs, ever. No really, just don't do it.
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## Curly Braces
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Always use curly braces when using the keywords `if/else/else if`. This prevents a lot of ambiguity and will prevent syntax errors in some edge cases.
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Bad:
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if (foo) bar();
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Good:
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if (foo) { bar(); }
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## Curly Braces Everywhere!
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Space After `function` Keyword, Except in Anonymous Functions
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Good:
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function foo() {
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}
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var foo = function() {
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// ...
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};
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Bad:
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function foo ()
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{
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// ...
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}
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var foo = function () {
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// ...
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};
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## Comments
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* no inline comments
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* single space after `//`
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* Do not use multiline comment `/* */`, we are reserving these for use with jsDocs.
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## Keywords
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* space immediately after if, else, while, etc
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* opening curly brace should always be on the same line.
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Good:
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if (true) {
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// do the thing
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}
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Bad:
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if(true)
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{
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// do the thing
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}
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## Else
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Avoid else and "end early". In JavaScript there is often a lot of indenting (usually when dealing with async code and named "callback hell"). Anything you can do reduce the number of indents should be done. One thing is to <a href='http://blog.timoxley.com/post/47041269194/avoid-else-return-early' target='_blank' rel='nofollow'>avoid the else</a> keyword.
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This also has the side effect of making code cleaner and easier to read.
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Bad:
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someAsynFunc(function(err, data) {
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if (err) {
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callback(err);
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} else {
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// do stuff with data
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}
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});
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Good:
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someAsynFunc(function(err, data) {
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if (err) {
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return callback(err);
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}
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// do stuff with data
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// saves one indent
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});
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## Long Strings
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Long multiline strings should be in one of two forms:
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var longString =
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‘long strings should ‘ +
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‘be in this form, with the ‘ +
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‘operator ending the line’;
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var foo = 'bar';
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var longString = [
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'long strings with variables such as ',
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foo,
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'should ',
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'be in this form, an array of strings ',
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'that are joined with the join array instance method',
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].join('');
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...more to come |