Re^2: Ternary if versus normal if question

Why shouldn't you? Perl idiom says that:

(.5<rand) or die "horribly";
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is acceptable. In fact even encouraged. Can you explain to OP and others why your very compact and easily read example is so much worse than:

if (.5<rand) {
    print "Wow\n";
} else {
    die "horribly";
}
[download]

Granted, were the string in either case much bigger, or were more lines of code required than shown in either case, if starts to look much better. Even better however would be the or die idiom.

However, this doesn't really apply to OP's context where $var = <cond> ? <case 1> : <case 2>; is ok and $var = ! $var; is much better.

DWIM is Perl's answer to Gödel

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Re^3: Ternary if versus normal if question by blazar (Canon) on Nov 18, 2005 at 07:53 UTC
Why shouldn't you? Perl idiom says that: `(.5<rand) or die "horribly";` [download] is acceptable. In fact even encouraged. Can you explain to OP and others why your very compact and easily read example is so much worse than: It is worse in that short circuiting `or` used in contexts like the one you're referring to makes for very clear syntax imitating its use in natural languages. Indeed the practical rule of a thumb is to use low-precedence logical operators for flow control and high-precedence ones to operate on values. Of course there are reasonable situations in which it is reasonable to violate this "rule", but in most cases it does apply. `if (.5<rand) { print "Wow\n"; } else { die "horribly"; }` [download] To be fair I happen rarely enough to (have to) use a full `if` ... `then` ... `else` construct like the above. In this case, for example `die "horribly" if .5 < rand; print "Wow\n";` [download] would suffice. Of course this is specific of the particular example under examination, but I make a frequent use of blocks (sometimes also `for` loops having the sole purpose of aliasing to `$_`) and of last, next, and more rarely redo and they make for quite as compact but still perfectly readable syntax.	[reply] [d/l] [select]

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Re^3: Ternary if versus normal if question
by blazar (Canon) on Nov 18, 2005 at 07:53 UTC

Why shouldn't you? Perl idiom says that:
(.5<rand) or die "horribly";
[download]
is acceptable. In fact even encouraged. Can you explain to OP and others why your very compact and easily read example is so much worse than:

It is worse in that short circuiting or used in contexts like the one you're referring to makes for very clear syntax imitating its use in natural languages. Indeed the practical rule of a thumb is to use low-precedence logical operators for flow control and high-precedence ones to operate on values. Of course there are reasonable situations in which it is reasonable to violate this "rule", but in most cases it does apply.

if (.5<rand) { print "Wow\n"; } else { die "horribly"; }
[download]

To be fair I happen rarely enough to (have to) use a full if ... then ... else construct like the above. In this case, for example

die "horribly" if .5 < rand;
print "Wow\n";
[download]

for

$_

last

redo

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