merge-concat

merge-concat

Merge an array of objects and concatenate values based on a function

install

$ npm install merge-concat

usage

var merge = require('merge-concat')
 
var data = [{
    a:'red',
    b:'blue'
},{
    b:'green'
}]
 
var flat = merge(data)
 
console.dir(flat)

This would print

{
    a:'red',
    b:'green'
}

concatfn

You can supply a second function that decides on how to handle overwrites

For example - if a value starts with 'b' we can ensure it is never overwritten:

var flat = merge(data, function(prev, next, field){
    return prev.charAt(0)=='b' ? prev : next
})
 
console.dir(flat)

This would print

{
    a:'red',
    b:'blue'
}

This lets you concatenate previous values based on custom logic:

var flat = merge(data, function(prev, next, field){
    return prev.charAt(0)=='b' ? prev + ',' + next : next
})
 
console.dir(flat)

This would print

{
    a:'red',
    b:'blue,green'
}

api

merge(arr, function(prev, next, field){})

Get an object that merges the properties of the provided array - later objects take precedence.

If the concatfn is defined, it is called with the previous, next and field variables for each override.

The normal behaviour is to return next but you can use custom logic to decide how things are joined.

merge(arr, function(prev, next, field){
    if(prev.match(/\|\s*$/) || next.match(/^\s*\|/)){
        return prev + next
    }
    else{
        return next
    }
})
 

licence

MIT