Funktion chr() i Perl

I programmeringssproget Perl har en indbygget funktion chr(). Denne funktion returnerer det tegn, der svarer til det angivne nummer.

Her er et eksempel:

▶ Run
#!/usr/bin/perl

use utf8;
use open qw(:std :utf8);
use feature qw(say);

say chr('65'); # A
say chr('49'); # 1
say chr('1046'); # Ж

Argumenter

Hvis funktioner chr() videregiver ikke nogen argumenter for, at den fungerer med standard variable $_:

▶ Run
#!/usr/bin/perl

$_ = 98;

print chr(); # b

Har du brug for at passere nummer. Funktionen returnerer det tegn, der svarer til denne antal.

Hvis funktioner chr() pass mere end ét argument, vil det fejl:

▶ Run
#!/usr/bin/perl

print chr(99, 100);
Too many arguments for chr at script.pl line 3, near "100)"
Execution of script.pl aborted due to compilation errors.

Officiel dokumentation

Her er outputtet af kommandoen perldoc -f chr:

    chr NUMBER
    chr     Returns the character represented by that NUMBER in the
            character set. For example, "chr(65)" is "A" in either ASCII or
            Unicode, and chr(0x263a) is a Unicode smiley face.

            Negative values give the Unicode replacement character
            (chr(0xfffd)), except under the bytes pragma, where the low
            eight bits of the value (truncated to an integer) are used.

            If NUMBER is omitted, uses $_.

            For the reverse, use "ord".

            Note that characters from 128 to 255 (inclusive) are by default
            internally not encoded as UTF-8 for backward compatibility
            reasons.

            See perlunicode for more about Unicode.

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