My conscience caught up with me, here is a much cleaner way of doing it... 
#!/usr/local/bin/perl -wl
use strict;

sub my_printf {
    my $text = shift;
    $text =~ s/\%(.)/&replace_arg($1,\@_)/ge;
    return $text;
}

sub replace_arg {
    # takes in a replacement 'code' and an arg list ref
    # converts the code, poping from the arg list as needed

    # if you have more then 3 possible codes, you might want to
    # impliment this as a hash of code refs (aka: closures)
    
    my ($code, $args) = @_;
    if ('a' eq $code) {               # %a means flat substitution
    return shift @{$args};
    } elsif ('b' eq $code) {          # %b means length of the arg
    return length shift @{$args};
    }  elsif ('%' eq $code) {         # %% means %
    return '%';                   # note: no shift
    } # else...
    return "humina:$code?";

}

print my_printf("foo %a bar %b", "baz", "baz");
print my_printf("oy %%9");
print my_printf("the %a is %% %b", "probability", "foo bar");
print my_printf("ignoring %%100 of the unused args", "unused arg");

__END__
foo baz bar 3
oy %9
the probability is % 7
ignoring %100 of the unused args

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In reply to Re: Re: Accepting a template string and replacing placeholders the way printf does. by hossman
in thread Accepting a template string and replacing placeholders the way printf does. by ehdonhon

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