in reply to Optimizing Perl Code - single versus double quotes really that important?

Speed-wise, I don't think it makes much difference. (As has already been pointed out.) The fact that you could replace:

$info1 = "this is some sample stuff".$info_in."<br><br>";

print <<__ENDER__;
$info1
.
.
__ENDER__

[download]

With:

print <<__ENDER__;
this is some sample stuff $info_in <br><br>
.
.
__ENDER__

[download]

Which then suggests this:

$info[1] = "this is some sample stuff $info_in <br><br>";
..
foreach my $outfo ( @info ) {
   print "$outfo\n";
}

[download]

Might be something you want to look at to do some cleanup...

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Re^2: Optimizing Perl Code - single versus double quotes really that important?
by ikegami (Patriarch) on Feb 05, 2009 at 18:02 UTC

    Speed-wise, I don't think it makes much difference

    Speedwise, it makes no difference. They produce exactly the same code. 

    $ perl -MO=Concise,-exec -e'$x = qq{a $b c}'
1  <0> enter
2  <;> nextstate(main 1 -e:1) v
3  <$> const[PV "a "] s
4  <#> gvsv[*b] s
5  <2> concat[t3] sK/2
6  <$> const[PV " c"] s
7  <2> concat[t4] sKS/2
8  <#> gvsv[*x] s
9  <2> sassign vKS/2
a  <@> leave[1 ref] vKP/REFC
-e syntax OK

$ perl -MO=Concise,-exec -e'$x = q{a }.$b.q{ c}'
1  <0> enter
2  <;> nextstate(main 1 -e:1) v
3  <$> const[PV "a "] s
4  <#> gvsv[*b] s
5  <2> concat[t3] sK/2
6  <$> const[PV " c"] s
7  <2> concat[t4] sKS/2
8  <#> gvsv[*x] s
9  <2> sassign vKS/2
a  <@> leave[1 ref] vKP/REFC
-e syntax OK

    [download]
[reply]
[d/l]

      Well...

      perl -MO=Concise,-exec -e '$x=qq{a $b c}'
1  <0> enter
2  <;> nextstate(main 1 -e:1) v:{
3  <$> const[PV "a "] s
4  <#> gvsv[*b] s
5  <2> concat[t3] sK/2
6  <$> const[PV " c"] s
7  <2> concat[t4] sKS/2
8  <#> gvsv[*x] s
9  <2> sassign vKS/2
a  <@> leave[1 ref] vKP/REFC
-e syntax OK

perl -MO=Concise,-exec -e '$x=q{a $b c}'
1  <0> enter
2  <;> nextstate(main 1 -e:1) v:{
3  <$> const[PV "a $b c"] s
4  <#> gvsv[*x] s
5  <2> sassign vKS/2
6  <@> leave[1 ref] vKP/REFC
-e syntax OK

      [download]

      So obviously there is some minor difference at compile-time. (Which would be the only difference I expect.) Once compiled equivalent expressions produce equivalent op-code, it's just that the compile process isn't exactly the same.

      Unlikely to be noticeable though, and really irrelevant to my original reply.

[reply]
[d/l]
        Apples and oranges. Those snippets don't build the same string. Of course they result in different code.
[reply]

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