| index.jsView |
|---|
| 1 | + |
| 2 | +var readArray = exports.readArray = function (array) { |
| 3 | + var i = 0 |
| 4 | + return function (reader) { |
| 5 | + reader(function (end, cb) { |
| 6 | + if(end) |
| 7 | + return cb && cb(end) |
| 8 | + |
| 9 | + cb(i >= array.length || null, array[i++]) |
| 10 | + }) |
| 11 | + } |
| 12 | +} |
| 13 | + |
| 14 | +var count = function () { |
| 15 | + var i = 0 |
| 16 | + return function (reader) { |
| 17 | + return reader(function (end, cb) { |
| 18 | + if(end) return cb && cb(end) |
| 19 | + cb(null, i++) |
| 20 | + }) |
| 21 | + } |
| 22 | +} |
| 23 | + |
| 24 | +var destack = function (n) { |
| 25 | + var i = 0; n = n || 10, waiting = [], queued = false, ended = false |
| 26 | + return function (readable) { |
| 27 | + return function (reader) { |
| 28 | + return reader(function (end, cb) { |
| 29 | + ended = ended || end |
| 30 | + if(i ++ < n) { |
| 31 | + return readable(end, cb) |
| 32 | + } else { |
| 33 | + process.nextTick(function () { |
| 34 | + i = 0 |
| 35 | + readable(end, cb) |
| 36 | + }) |
| 37 | + } |
| 38 | + }) |
| 39 | + } |
| 40 | + } |
| 41 | +} |
| 42 | + |
| 43 | +var map = function (map) { |
| 44 | + map = map || function (e) {return e} |
| 45 | + return function (readable) { |
| 46 | + return function (reader) { |
| 47 | + return reader(function (end, cb) { |
| 48 | + readable(end, function (end, data) { |
| 49 | + cb(end, map(data)) |
| 50 | + }) |
| 51 | + }) |
| 52 | + } |
| 53 | + } |
| 54 | +} |
| 55 | + |
| 56 | +var drain = exports.drain = function (op) { |
| 57 | + return function (readable) { |
| 58 | + readable(null, function read (err, data) { |
| 59 | + if(err) return |
| 60 | + op && op(data) |
| 61 | + readable(null, read) |
| 62 | + }) |
| 63 | + |
| 64 | + } |
| 65 | +} |
| 66 | + |
| 67 | +var through = function () { |
| 68 | + return function (readable) { |
| 69 | + return function (reader) { |
| 70 | + return reader(function (end, cb) { |
| 71 | + return reader(end, cb) |
| 72 | + }) |
| 73 | + } |
| 74 | + } |
| 75 | +} |
| 76 | + |
| 77 | +function pipeable (_reader) { |
| 78 | + return function () { |
| 79 | + var args = [].slice.call(arguments) |
| 80 | + return function (readable) { |
| 81 | + args.unshift(readable) |
| 82 | + return function (reader) { |
| 83 | + return reader(_reader.apply(null, args)) |
| 84 | + } |
| 85 | + } |
| 86 | + } |
| 87 | +} |
| 88 | + |
| 89 | +var dumb = pipeable(function (readable, op) { |
| 90 | + return function (end, cb) { |
| 91 | + return readable(end, function (end, data) { |
| 92 | + op && op(data) |
| 93 | + cb(end, data) |
| 94 | + }) |
| 95 | + } |
| 96 | +}) |
| 97 | + |
| 98 | + |
| 99 | + |
| 100 | +var take = pipeable(function (readable, test) { |
| 101 | + var ended = false |
| 102 | + if('number' === typeof test) { |
| 103 | + var n = test; test = function () { |
| 104 | + return n-- > 0 |
| 105 | + } |
| 106 | + } |
| 107 | + return function (end, cb) { |
| 108 | + if(end) { |
| 109 | + if(!ended) return ended = end, readable(end, cb) |
| 110 | + cb(ended) |
| 111 | + } |
| 112 | + return readable(null, function (end, data) { |
| 113 | + if(end || !test(data)) return readable(end || true, cb) |
| 114 | + return cb(null, data) |
| 115 | + }) |
| 116 | + } |
| 117 | +}) |
| 118 | + |
| 119 | +var nextTick = process.nextTick |
| 120 | +var highWaterMark = pipeable(function (readable, highWaterMark) { |
| 121 | + var buffer = [], waiting = [], ended, reading = false |
| 122 | + highWaterMark = highWaterMark || 10 |
| 123 | + |
| 124 | + function read () { |
| 125 | + while(waiting.length && (buffer.length || ended)) |
| 126 | + waiting.shift()(ended, ended ? null : buffer.shift()) |
| 127 | + } |
| 128 | + |
| 129 | + function next () { |
| 130 | + if(ended || reading || buffer.length >= highWaterMark) |
| 131 | + return |
| 132 | + reading = true |
| 133 | + return readable(ended, function (end, data) { |
| 134 | + reading = false |
| 135 | + ended = ended || end |
| 136 | + if(data != null) buffer.push(data) |
| 137 | + |
| 138 | + next(); read() |
| 139 | + }) |
| 140 | + } |
| 141 | + |
| 142 | + process.nextTick(next) |
| 143 | + |
| 144 | + return function (end, cb) { |
| 145 | + ended = ended || end |
| 146 | + waiting.push(cb) |
| 147 | + |
| 148 | + next(); read() |
| 149 | + } |
| 150 | +}) |
| 151 | + |
| 152 | +function writeArray(cb) { |
| 153 | + var array = [] |
| 154 | + return function (readable) { |
| 155 | + ;(function next () { |
| 156 | + return readable(null, function (end, data) { |
| 157 | + if(end) return cb(end == true ? null : end, array) |
| 158 | + array.push(data) |
| 159 | + next() |
| 160 | + }) |
| 161 | + })() |
| 162 | + return function () { throw new Error('write-only') } |
| 163 | + } |
| 164 | +} |
| 165 | + |
| 166 | + |
| 167 | +var asyncMapSerial = pipeable(function (readable, map) { |
| 168 | + var reading = false |
| 169 | + return function (end, cb) { |
| 170 | + if(reading) throw new Error('one at a time, please!') |
| 171 | + reading == true |
| 172 | + return readable(end, function (end, data) { |
| 173 | + map(data, function (err, data) { |
| 174 | + reading = false |
| 175 | + |
| 176 | + |
| 177 | + }) |
| 178 | + }) |
| 179 | + } |
| 180 | +}) |
| 181 | +*/ |
| 182 | + |
| 183 | +if(!module.parent) |
| 184 | + |
| 185 | + count() |
| 186 | + (destack ()) |
| 187 | + (take(20)) |
| 188 | + (highWaterMark(2)) |
| 189 | + (writeArray(console.log)) |
| 190 | + |
| 191 | + |
| 192 | + |
| 193 | + return readable(null, function next (e, d) { |
| 194 | + if (e) return |
| 195 | + return readable(e, next) |
| 196 | + }) |
| 197 | + })*/ |
| 198 | + |
| 199 | + |
| 200 | + |