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examples | ||
test | ||
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LICENCE | ||
index.js | ||
package.json | ||
readme.markdown |
readme.markdown
MapStream
Refactored out of event-stream
##map (asyncFunction[, options])
Create a through stream from an asyncronous function.
var map = require('map-stream')
map(function (data, callback) {
//transform data
// ...
callback(null, data)
})
Each map MUST call the callback. It may callback with data, with an error or with no arguments,
-
callback()
drop this data.
this makes the map work likefilter
,
note:callback(null,null)
is not the same, and will emitnull
-
callback(null, newData)
turn data into newData -
callback(error)
emit an error for this item.
Note: if a callback is not called,
map
will think that it is still being processed,
every call must be answered or the stream will not know when to end.Also, if the callback is called more than once, every call but the first will be ignored.
##Options
failures
-boolean
continue mapping even if error occured. On errormap-stream
will emitfailure
event. (default:false
)