Writing a program to rename copied photos throughout several folders I am using several greps, at one stage I needed to filter a folder, rather than add another layer of grep I placed an if conditional inside an anonymous list constructor, and discovered that the ?: tertiary conditional may not actually be a synonym for if.

There is most likely a simple reason why the if statement(term/expression?) produces a syntax error if used inside a refto/list constructor, but I wondered if this was due to greater reason than being condusive to writing better code? (as in, hint: use if to control flow not determine variables)

from my examples here, I summise that the tertiary conditional is an if statement(term/expression), wrapped in a do block. Is this the case? 

my @arr =     ( if(1<2){'1'}else{()} );          #syntax error
my $arrref =  \( if(1<2){'1'}else{()} );         #syntax error

my $arrref2 = [  1<2 ? '1' : () ];               #works
my @arr2 =    ( do { if(1<2){'1'}else{()} } );   #works


if(1<2){print '1',$/ }else{print '2',$/};        #works
1<2 ? print '1',$/ : print '2',$/;               #works
( 1<2 ? print '1',$/ : print '2',$/ );           #works

( if(1<2){print '1',$/ }else{print '2',$/} );    #syntax error

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In reply to conditional statements in list constructors by Don Coyote

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