功能 chr() Perl

在Perl编程语言都有一个内置的功能 chr(). 这一功能将返回字,对应于指定的数量。

这里有一个例子:

▶ 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

参数

如果功能 chr() 不通过任何论点、功能适用 默认的变量 $_:

▶ Run
#!/usr/bin/perl

$_ = 98;

print chr(); # b

特你需要通行证的数量。 该功能将返回字,对应于此 数。

如果功能 chr() 通过多个参数,它将错误:

▶ 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.

官方文件

这里是输出的命令 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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