Re^6: Short form (ternary) if else

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Re^7: Short form (ternary) if else by wrog (Friar) on Feb 08, 2012 at 23:32 UTC
operator precedence; `? :` binds tighter than `=`. So `1 ? $x=1 : $x=0` really means `(1 ? $x=1 : $x)=0` which is then the same as `($x=1)=0` which is why $x becomes 0. You can use assignments within `? :`, you just need to parenthesize them `1 ? $x=1 : ($x=0)`	[reply] [d/l] [select]
Re^8: Short form (ternary) if else by Riales (Hermit) on Feb 08, 2012 at 23:43 UTC
Ah, perfect explanation. I knew it had something to do with operator precedence but I just couldn't work out quite where it was happening. Thank you, good sir!	[reply]
Re^7: Short form (ternary) if else by kcott (Archbishop) on Feb 08, 2012 at 23:59 UTC
Adding parentheses to the second statement to show precedence, we get: `( 1 ? ( $x=1 ) : $x ) = 0;` [download] As the 2nd and 3rd arguments are lvalues, you can assign to the ternary operator. As the first argument (`1`) is TRUE, the assignment becomes: `( $x=1 ) = 0;` [download] Which effectively boils down to: `$ perl -Mstrict -Mwarnings -E 'my $x; ($x = 1) = 0; say $x;' 0` [download] The link I gave above (perlop manpage - under Conditional Operator) has a fuller description. -- Ken	[reply] [d/l] [select]
Re^8: Short form (ternary) if else by gg48gg (Sexton) on Feb 09, 2012 at 00:05 UTC
Thanks all! I got my question answered and then some. Good discussion.	[reply]