markjugg-- using int to test numberness

I think using 'int' does a good job of this:

print "is number" if int($test);
[download]

If $test = '5.55555' it works, but if $test = 'howdy', it doesn't.

-mark

Comment on markjugg-- using int to test numberness Download Code

Replies are listed 'Best First'.
RE: markjugg-- using int to test numberness by extremely (Priest) on Oct 25, 2000 at 08:44 UTC
Um, no... this is bad... `perl -e 'print "yikes\n" if int("1upmanship")' perl -e 'print "Zero is a number.\n" if int("0")'` [download] prints yikes! but not the "Zero..." line. `int()` doens't test a number it truncates it to integer form. And since the number 0 is false the second line doesn't work. Treating a string that starts with numeral as a number causes perl to whack off the text and use the number. OUCH! -- $you = new YOU; honk() if $you->love(perl)	[reply] [d/l]

Replies are listed 'Best First'.

RE: markjugg-- using int to test numberness
by extremely (Priest) on Oct 25, 2000 at 08:44 UTC

perl -e 'print "yikes\n" if int("1upmanship")'
perl -e 'print "Zero is a number.\n" if int("0")'
[download]

prints yikes! but not the "Zero..." line. int() doens't test a number it truncates it to integer form. And since the number 0 is false the second line doesn't work. Treating a string that starts with numeral as a number causes perl to whack off the text and use the number. OUCH!

--
$you = new YOU;
honk() if $you->love(perl)

[reply]
[d/l]