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
-
Are you posting in the right place? Check out Where do I post X? to know for sure.
-
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
<u> <ul>
-
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
intervention).
-
Want more info? How to link
or How to display code and escape characters
are good places to start.