They both "visit" each element of a list (I would say, they both execute a block of code for each element of a list). The main difference is that for is a statement, map is an expression. As such, map has (in non-void context) a return value.

Only if you assign the return value of map to an array, and you have the same array as input list to the map, one could say that map 'transforms' a list. But then it's the combination of map and the assign statement.

The only way I can think of map on its own "transforming" a list is constructs like: 

    map {$_ = ucfirst} @array;

[download]
But for knows that trick as well: 
    for (@array) {$_ = ucfirst}

[download]

In reply to Re^2: Map Vs Foreach by JavaFan
in thread Map Vs Foreach by perlCrazy

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