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Other implementations
import "strings"
lowerS, lowerWord := strings.ToLower(s), strings.ToLower(word)
ok := strings.Contains(lowerS, lowerWord)
ok = s.match?( /#{word}/i )
OK := Pos(LowerCase(AWord), LowerCase(S)) > 0;
import std.string;
ok = indexOf(word, s, != -1;
import Data.Char (toLower)
import Data.List (isInfixOf)
containsIgnoreCase :: String -> String -> Bool
containsIgnoreCase s word = isInfixOf (map toLower word) (map toLower s)
ok = word.lower() in s.lower()
extern crate regex;
use regex::Regex;
let mut re = String::with_capacity(4 + word.len());
re += "(?i)";
re += word;
let re = Regex::new(&re).unwrap();
ok = re.is_match(&s);