in reply to Re: scope of variables in a sub
in thread scope of variables in a sub

Well spotted! Assignment in an if condition is just too smelly for my brain to process.

Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond

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Re^3: scope of variables in a sub
by tobyink (Canon) on Sep 24, 2020 at 10:29 UTC

    Assignment in an if is fine if you're doing:

    if ( my $var = something() ) {
  # use $var here
}

    [download]

    (Ditto while.)

    But if $var has a wider scope, it's probably a bad idea.

    toby döt ink
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      Even then there are two major issues to my mind:

      1. The clutter around the assignment hides the assignment making it harder to see where the variable gets its value
      2. It is easy to confuse = and == so using the assignment operator in a conditional expression makes code harder to maintain

      Point 2 is seen as sufficient of an issue that many compilers generate warnings for assignment in conditional expressions. I love the way that Perl allows terse functional chords that allow the equivalent of many lines of code in other languages to be wrapped up in a single compact statement. But playing tricks with side effects just to save a line of code doesn't sit well with me.

      I'm completely fine with the equivalent assignment in a while statement though - go figure.

      Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond
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Re^3: scope of variables in a sub
by perlfan (Parson) on Sep 24, 2020 at 02:56 UTC
    >Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond

    Yup. OP must be doing just this. xD

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