19 lines
600 B
Ruby
19 lines
600 B
Ruby
|
# Some useful additions to the String class
|
||
|
|
|
||
|
|
class String
|
||
|
|
|
||
|
|
def is_utf8?
|
||
|
|
self =~ /^(
|
||
|
|
[\x09\x0A\x0D\x20-\x7E] # ASCII
|
||
|
|
| [\xC2-\xDF][\x80-\xBF] # non-overlong 2-byte
|
||
|
|
| \xE0[\xA0-\xBF][\x80-\xBF] # excluding overlongs
|
||
|
|
| [\xE1-\xEC\xEE\xEF][\x80-\xBF]{2} # straight 3-byte
|
||
|
|
| \xED[\x80-\x9F][\x80-\xBF] # excluding surrogates
|
||
|
|
| \xF0[\x90-\xBF][\x80-\xBF]{2} # planes 1-3
|
||
|
|
| [\xF1-\xF3][\x80-\xBF]{3} # planes 4-15
|
||
|
|
| \xF4[\x80-\x8F][\x80-\xBF]{2} # plane 16
|
||
|
|
)*$/x;
|
||
|
|
end
|
||
|
|
|
||
|
|
end
|