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Re^3: Different behaviors between "while" and "map"

by betterworld (Curate)
on Dec 06, 2008 at 01:42 UTC ( [id://728454]=note: print w/replies, xml ) Need Help??


in reply to Re^2: Different behaviors between "while" and "map"
in thread Different behaviors between "while" and "map"

It helps to know that the loop is expanded to:

while ($_ = <SOME_FILE_HANDLE>){
   ...
}

[download]

This shows that <...> is nothing more than a loop condition: the loop body is executed immediately after each evaluation of the <...> operator. This is how a while loop works.

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Re^4: Different behaviors between "while" and "map"
by JavaFan (Canon) on Dec 06, 2008 at 02:18 UTC
    Not for the last 12 years or so. It's expanded to 
    while (defined ($_ = <SOME_FILE_HANDLE>)) {
    ...
}

    [download]
[reply]
[d/l]

      Technically, you're both right, because 

      while ($_ = <SOME_FILE_HANDLE>){
   ...
}

      [download]
      is expanded to 
      while (defined ($_ = <SOME_FILE_HANDLE>)) {
   ...
}

      [download]

      But all this is irrelevant. It's not the magical expansion of <> that causes the scalar context.

[reply]
[d/l]
[select]

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