As far as I can tell, if (1==1) { } is being used as an alternative to commenting out the lines. While this may provide a simple way to skip a block of code by changing a single character, there appears to be a performance detriment: 

#!/usr/bin/perl -w

use strict;

if (1==1) { 1; }

[download]
$ perl -MO=Deparse equal

BEGIN { $^W = 1; }
use strict 'refs';
do {
    '???':
};

[download]
#!/usr/bin/perl -w

use strict;

if (0==1) { 1; }

[download]
$ perl -MO=Deparse unequal

BEGIN { $^W = 1; }
use strict 'refs';
do {
    '???'
};

[download]
#!/usr/bin/perl -w

use strict;

if (1==0) { 1; }

[download]
$ perl -MO=Deparse unequal2

BEGIN { $^W = 1; }
use strict 'refs';
do {
    '???'
};

[download]

#!/usr/bin/perl -w

use strict;

1;

[download]
$ perl -MO=Deparse uncommented

BEGIN { $^W = 1; }
use strict 'refs';
'???':

[download]
#!/usr/bin/perl -w

use strict;

# 1;

[download]
$ perl -MO=Deparse commented

BEGIN { $^W = 1; }

[download]

UPDATE: Added the if (1==1) { } corollary

In reply to Re^2: Badly need to call a function...:-) by eibwen
in thread Badly need to call a function...:-) by Mabooka-Mabooka

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