Re: map and grep one-liner problem

TIMTOWDI (I had some time to kill :-)

I assume your 'keys' are unique.*

my @ta = ( 'a x', 'b y', 'c z' );
my $key = 'b';

printf "key=%s, value=%s\n", map split, grep { ! index $_, $key . ' ' 
+} @ta;
printf "key=%s, value=%s\n", $key, ${{ map split, @ta }}{$key};
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* If not, the first snippet will select the first hit, while the second will give you the last hit.

Update: I could of course have simplified the second snippet further:

printf "key=%s, value=%s\n", $key, { map split, @ta }->{$key};

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Re^2: map and grep one-liner problem by jeanluca (Deacon) on Mar 14, 2007 at 14:18 UTC
This is really getting close to unreadability :) There is one thing in the first printf that I don't understand: `index $_, $key . ' '` What exactly does the last part do ( `. ' '` ), adding a space ? why ? LuCa	[reply] [d/l] [select]
Re^3: map and grep one-liner problem by Not_a_Number (Prior) on Mar 14, 2007 at 14:38 UTC
What exactly does the last part do `( . ' ' )`, adding a space ? Yes, that's exactly what it does. Otherwise, as johngg points out above, a search for 'b' will match not just 'b', but also, for example, 'bbking'. And if you look closely at this line in Anno's solution: `my @values = map / (.*)/, grep /^$key /, @ta;` you'll see that he does the same thing (note the space after `^$key` ?)	[reply] [d/l] [select]
Re^4: map and grep one-liner problem by jeanluca (Deacon) on Mar 14, 2007 at 16:48 UTC
I see! Your one-liners confused me, they are hard to read :) Thnx a lot! LuCa	[reply]