8061ecf0e2
* Move analytics initialization into docs.coffee * Bump Bootstrap and CodeMirror versions * Update output * Merge CodeMirror styles * Update CodeMirror styles * Better flexbox layout for docs, including flex auto-sized sidebar and main column * Minor styling fixes for Edge * Fix scrollspy for new layout * Update output * Clicking on the CoffeeScript logo in the navbar should scroll to top; fix main column width on mobile * Update output * 2.3.0 changelog * Update operators section for ** * Update docs for ES2018 object rest/spread * Remove references to Node's experimental modules support * Move the README coffee cup to the right side, so our name isn't cut off on the NPM page; update README and CONTRIBUTING text * Update dependencies * Add compatibility note for async generators * Bump version to 2.3.0 and update output * Have CI test in Node 10 instead of 9 * Somehow this gets generated slightly differently in Node 10 * Fix #4042: Update broken link
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Operators and Aliases
Because the == operator frequently causes undesirable coercion, is intransitive, and has a different meaning than in other languages, CoffeeScript compiles == into ===, and != into !==. In addition, is compiles into ===, and isnt into !==.
You can use not as an alias for !.
For logic, and compiles to &&, and or into ||.
Instead of a newline or semicolon, then can be used to separate conditions from expressions, in while, if/else, and switch/when statements.
As in YAML, on and yes are the same as boolean true, while off and no are boolean false.
unless can be used as the inverse of if.
As a shortcut for this.property, you can use @property.
You can use in to test for array presence, and of to test for JavaScript object-key presence.
In a for loop, from compiles to the ES2015 of. (Yes, it’s unfortunate; the CoffeeScript of predates the ES2015 of.)
To simplify math expressions, ** can be used for exponentiation and // performs floor division. % works just like in JavaScript, while %% provides “dividend dependent modulo”:
codeFor('modulo')
All together now:
| CoffeeScript | JavaScript |
|---|---|
is |
=== |
isnt |
!== |
not |
! |
and |
&& |
or |
` |
true, yes, on |
true |
false, no, off |
false |
@, this |
this |
a in b |
[].indexOf.call(b, a) >= 0 |
a of b |
a in b |
for a from b |
for (a of b) |
a ** b |
a ** b |
a // b |
Math.floor(a / b) |
a %% b |
(a % b + b) % b |
codeFor('aliases')