| Op | JS | Notes | Questions |
|---|---|---|---|
| (def x 42) | cljs.my.ns[‘x’] = 42 | Following gclosure module system | No vars? Compilation-time representation of ns? |
| cljs.my.ns.x = 42 | only this one will get minified | but this precludes special chars in names | |
| def returns var in Clojure, no var here | |||
| (fn [x y] …) | (function (x, y) {…}) | never do named function, use anon + def | Use for closures too? |
| (fn [x y] … (recur…) | rewrite as fn + nested loop | require analysis to transmit recur fact up | |
| rewrite when? | |||
| block always in return context | access to this for methods? | ||
| (if test then else) | (test ? then : else) | ||
| (do e1 e2 e3) | cljs.dofn(e1,e2,e3) | dofn returns last arg, allocs array? | requires js bootstrap file? |
| no, forces all to be exprs | no fn needed when not expr context | ||
| (function () {e1;e2;return e3;})() | |||
| expr context becomes return except when | |||
| single expr | |||
| (let [x 1 y 2] …) | (function [x,y] {…})(1, 2) | need to create nested functions for let* | how to detect ref to earlier? |
| var x__42 = 1;var y__43 = 2; … | var numbering | statement/expr dichotomy if inline? | |
| (function [] | could wrap in no-arg function always | needed for expr anyhow | |
| {var x = 1; var y = 2; …})() | if always wrapped, don’t need numbers? | can we do var x = 42; var x = 43? | |
| might still when nested | yes, but not var x = 42 …nesting… var x = x | ||
| expr always becomes return context | |||
| (. x y) | x.y or x.y()? | no type info to distinguish | bigger problem, both calling and retrieving |
| fn in slot are viable, Clojure says method wins | |||
| (. x y …) | x.y(…) | ||
| (: x y) ? | x.y | make all calls, add special field accessor | |
| x.y | x.y | . not used for classes in JS | so not global, but scoped? |
| can’t test from Clojure | but would want resolution of first segment to locals | ||
| what do macros use? | |||
| (. x (y)) | already defined for this case | wasn’t going to carry this into cljs, but | no arg == field, penalize no-arg methods? |
| ((. x y)) | more correct, it’s a slot | rationale, it’s not a method, just a slot, | |
| (-> (. x y) ()) | doesn’t currently work, could | but then why do the arg-taking ones work? | |
| (set! (. x y) 42) | x.y = 42 | whither vars and binding?? | |
| (set! some.global.x 42) | some.global.x = 42 | ||
| (loop [bindings] | while(true){ | wrap in function? depends on context | |
| … (recur)) | … rebind-continue | ||
| ret=xxx;break;} | |||
| (deftype Foo [a b c]) | my.ns.Foo = function(a,b,c) | turn inline defs into explicit extends? | deftype inline methods split out arities |
| {this.a = a;…this.c=c;} | can’t access this and fields. | ||
| in locals map, bind a to this.a etc | |||
| (new Foo 1 2 3) | (new Foo(1,2,3)) | ||
| (defprotocol P | my.ns.foo = function(obj args) | How to extend built-ins, default, nil, undefined | |
| (foo [args])) | {obj[‘my.ns.foo’](obj, args);} | can’t minify | |
| obj.my$ns$foo(obj, args) | |||
| P.ns = ‘my.ns’ | this only compile-time need, but compiler | ||
| not in js world, can’t see it | |||
| Require fully qualified protocol names? | |||
| (extend Foo my.ns.P | for each fn in map: | if no reified protocols, extend can’t be | or use Object.defineProperty to add method to |
| {:foo (fn [foo]…)} | Foo.prototype[‘my.ns.foo’] = fn | a function, unless protocol quoted | prototype? can then set enumerable to false |
| Foo.prototype.my$ns$foo = fn | or string | ||
| if extend is a macro or special, could | |||
| still evaluate fn map, but then can’t be | |||
| minified | |||
| evaluated extend requires maps, keywords | |||
| high bar for bootstrap if protocols | |||
| at bottom - extend* unevaluated? | |||
| make extend-type primitive instead? YES | |||
| constants | |||
| nil | null | ||
| “foo”, true, false, 42.0 | same | ||
| 42 | goog.Long? | ||
| ‘foo | symbol ctor | ||
| :foo | ? | how to do keyword interning? | |
| don’t want intern every reference | |||
| (ns my.ns | |||
| (:require [foo.bar :as fb]…) | |||
| (:macros [my.macros :as mm]…)) | :require-macros? |
svn co http://v8.googlecode.com/svn/trunk v8 cd v8/ scons console=readline d8
svn checkout http://closure-library.googlecode.com/svn/trunk/ closure-library