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Normal strings contain characters with character codes between 0 and 255, so-called 8-bit characters. But Pike can also handle strings with characters with higher character codes. This is needed for some languages, such as Japanese. Such strings are called wide strings:

"The character \x123456 is the same as \d1193046."

This string contains two occurrences of the character with (decimal) character code 1193046. As you may remember, Pike will translate \x followed by a hexadecimal (that is, base 16) number in a string literal to the character with that character code. The same is true for \d followed by a decimal (that is, normal base 10) number, and for a single \ followed by an octal (base 8) number.

Internally, Pike will handle wide strings differently from normal 8-bit strings, but as a Pike programmer, you will usually not need to worry about the difference. Just use the characters you need. There may however be some operations, for example certain methods in certain modules, that cannot handle wide strings but that work with 8-bit strings.

Here are some functions that can be used to examine wide strings:

  • String.width(string data)

    This gives the width of the string data. This width of a string is the number of bits that is used to store each character in the string. Normal strings are 8 bits wide, but strings can also be 16 or 32 bits wide. For each string, Pike will use as few bits as possible. For example, "foo" will be 8 bits wide, "foo\d255" is also 8 bits wide, "foo\d256" is 16 bits wide, and "foo\d70000" is 32 bits wide.

  • string_to_utf8(string data)

    This translates the string data, which can be a wide string, to a string in the format UTF8. UTF8 is a format that encodes wide characters in an 8-bit string.

  • utf8_to_string(string utf8_encoded_data)

    This translates an UTF8-encoded string utf8_encoded_data (which, by implication of the nature of the coding, can not be a wide string, since the UTF8 encoding is 8-bit by definition), to a pike string.