fa

fa = (concurrency=Number.MAX_VALUE, do_all=false, with_index=false) -> process ?= {} process.nextTick ?= (cb) -> cb() api = {} api.reduce = (arr, memo, iterator, callback) -> isArray = Array.isArray(arr) try keys = if isArray then arr else Object.keys(arr) catch e return callback(new Error("Trying to reduce over non iterable")) return callback(undefined, memo) unless keys.length errs = [] if do_all size = pending = keys.length count = 0 theCallback = (err, result) -> if err if errs errs.push(err) else callback(err) callback = -> return else if --pending == 0 err = if errs and errs.length then errs else undefined return callback(err,result) process.nextTick -> # use nextTick to avoid blowing the call stack nextItem(result) nextItem = (memo) -> if isArray val = arr[count++] iterator memo, val, theCallback else key = keys[count++] val = arr[key] iterator memo, val, key, theCallback nextItem(memo) nullFn = -> undefined tmpl = (name, initResults, single_argument_callback, handleResult, handleReturn) -> return (arr, iterator, callback, what=0) -> isArray = Array.isArray(arr) keys = if isArray then arr else Object.keys(arr) results = initResults() if !keys.length if single_argument_callback return callback(results) else return callback(undefined, results) errs = [] if do_all workers = 0 size = pending = keys.length count = 0 finished = false theCallback = (val,index) -> (err, result) -> # console.log("callback result", result) workers -= 1 if single_argument_callback result = err err = null if err if errs errs.push(err) else callback(err) callback = -> return else results = handleResult(results, result, val, index, callback) if results == true callback = -> finished = true return if --pending == 0 err = if errs and errs.length then errs else undefined if handleReturn return handleReturn(err, callback, results, size) else return callback(err,results) process.nextTick -> nextItem() nextItem = -> # console.log("process",pending,concurrency,count,isArray) if workers++ < concurrency and count < size and !finished index = count++ if isArray val = arr[index] if with_index iterator val, index, theCallback(val, index) else iterator val, theCallback(val, index) else key = keys[index] val = arr[key] if with_index iterator val, key, index, theCallback(val,index) else iterator val, key, theCallback(val,index) nextItem() for i in [1..(if concurrency < pending then concurrency else pending)] api.each = tmpl('each',nullFn,false,nullFn) # produce a new array of values api.map = tmpl('map', (() -> []), false, (results, result, val, index) -> results[index] = result results ) # produce a new array of values by concatting results together api.concat = tmpl('concat', (() -> []), false, (results, result) -> if Array.isArray(result) then results.concat(result) else results ) # return an array of values that pass a truth test. alias select api.filter = tmpl('filter', (() -> []), true, (results, result, val) -> results.push(val) if result results ) # return an array of values that the truth test passes. opposite of filter. api.reject = tmpl('reject', (() -> []), true, (results, result, val) -> results.push(val) unless result results ) # first value that passes a truth test api.detect = tmpl('detect', (() -> undefined), true, (results, result, val, index, callback) -> results = 0 if results==undefined if result callback(val, results) return true ++results ) # return true if any of the values pass the truth test (short circuits if true is found) api.any = tmpl('any', (() -> false), true, ((results, result, val, index, callback) -> if result callback(true) true ), (err, callback) -> callback(false) ) # return true if all of the values pass the truth test api.all = tmpl('all', (() -> true), true, ((results, result, val, index, callback) -> results = 0 if results==true if result then ++results else results ), (err, callback, results, size) -> callback(results == size) ) # # Moderator functions -- modify how the iterators behave # api.queue = (concurrency) -> fa(concurrency, do_all, with_index) api.series = -> fa(1, do_all, with_index) api.with_index = -> fa(concurrency, do_all, true) api.continue = -> fa(concurrency, true, with_index) # aliases api.forEach = api.each api.select = api.filter api.find = api.detect api.inject = api.reduce api.foldl = api.reduce api.some = api.any api.every = api.all api.concurrent = api.queue api.c = api.queue api.if = (conditional, trueFn, elseFn, callback) -> if !callback callback = elseFn elseFn = null if conditional trueFn callback else if elseFn elseFn callback else callback() api if typeof(module) != 'undefined' module.exports = fa() else window.fa = fa()