Re^2: Common Perl Idioms

An alternative to your &find_first_index that I prefer (for smaller lists) is

    use List::Util 'first';

    sub find_first_index {
        my $target = shift;
        first { $_[$_] eq $target } 0 .. $#_;
    }

    # Simple enough to write inline:

    my $idx = first { $ary[$_] eq $target } 0 .. $#ary;
[download]

I don't know about any efficiency issues though.

Update: Fixed a off-by-one bug in the sub and added parenthesis.

ihb

Read argumentation in its context!

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Re^3: Common Perl Idioms by demerphq (Chancellor) on Jul 24, 2004 at 02:47 UTC
I don't know about any efficiency issues though. Doesn't look good: Read more... (2 kB) `Rate ihb_zip ihb_hit dmq_zip dmq_hit ihb_zip 8461/s -- -5% -44% -50% ihb_hit 8869/s 5% -- -42% -47% dmq_zip 15177/s 79% 71% -- -10% dmq_hit 16782/s 98% 89% 11% --` [download] And thats using the XS List::Util implementation from 5.8.2. Theres a lot of overhead in calling the closure, and I think that the range operator isn't lazy in this usage, so it has to manufacture a list of indexes to use. --- demerphq _{First they ignore you, then they laugh at you, then they fight you, then you win. -- Gandhi}	[reply] [d/l] [select]
Re^4: Common Perl Idioms by BrowserUk (Patriarch) on Jul 24, 2004 at 03:35 UTC
`sub firstIdx { $_[ $_ ] eq $_[ 0 ] and return --$_ for 1 .. @_; return; }` [download] Examine what is said, not who speaks. "Efficiency is intelligent laziness." -David Dunham "Think for yourself!" - Abigail "Memory, processor, disk in that order on the hardware side. Algorithm, algoritm, algorithm on the code side." - tachyon	[reply] [d/l]