I'm not sure exactly what you mean by isachar, since that doesn't appear to be one of the ANSI C standard functions. However, taking Zaxo's code one step further: 
sub isachar
{
    return pop =~ /^[\x00-\x7F]/;
}

# Or alternatively
sub isalnum
{
    return pop =~ /^\w/;
}

# As in:
$is = isachar('a');

[download]
Update:
crazyinsomiac pointed out "pop is not a variable", but it is a quick way of retrieving the first element of @_, a.k.a. $_[0].

In reply to Re: isachar() equivalent? by tadman
in thread isachar() equivalent? by jroberts

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