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luijar/lens-arr-head.js

Created September 26, 2015 21:56
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Avoid side effect with lenses
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lens-arr-head.js
var headLens = R.lensIndex(0); // point to first element in the array
R.view(headLens, people); //=> ana
var array2 = R.set(headLens, 'OLIVIA', firstnames); //=> ["OLIVIA", "LUIS", "CARLOS", "NESTOR", "MARIA"]
R.over(headLens, R.toLower, array2); //=> ["olivia", "LUIS", "CARLOS", "NESTOR", "MARIA"]
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