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@sheldonh
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CoffeeScript Object.merge
merge = (xs...) ->
if xs?.length > 0
tap {}, (m) -> m[k] = v for k, v of x for x in xs
tap = (o, fn) -> fn(o); o
console.log merge {foo: '1', bar: 'baz'}, {bar: 'bis'} , {wombat: 'fishpaste'}
###
{ foo: '1', bar: 'bis', wombat: 'fishpaste' }
###
@pke
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pke commented Aug 16, 2014

Thanks, very neat. And works, unlike the CoffeeScript helper method displayed here http://coffeescript.org/documentation/docs/helpers.html
Which is strange, since its part of the compiler... hmmm

@bogdan
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bogdan commented Nov 23, 2015

Nice, I can make it even more neat:

merge=(xs... ->
  if xs?.length>0
    tap {},(m)->m[k]=v for k,v of x for x in xs
tap=(o, fn)->fn(o);o

But thanks anyway.

@alexbfree
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This is really handy - thanks. Could you explain line 5? I didn't know semi-colon was allowed in coffeescript....

@thislooksfun
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@alexbfree Semicolons are fully optional in CS. (console.log "hi" and console.log "hi"; are both 100% valid), but they are still the only way to fit multiple statements on the same line.

To quote the coffeescript website directly:
"You don’t need to use semicolons ; to terminate expressions, ending the line will do just as well (although semicolons can still be used to fit multiple expressions onto a single line)." (source)

@sixtyfive
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The version by @bogdan (23 Nov 2015) unfortunately doesn't compile for me. The original version works fine, though.

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