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TS JS Deno

Returns true if the string is y/yes or false if the string is n/no.

Use RegExp.test() to check if the string evaluates to y/yes or n/no. Omit the second argument, def to set the default answer as no.

const yesNo = (val: string, def = false) =>
/^(y|yes)$/i.test(val) ? true : /^(n|no)$/i.test(val) ? false : def;
yesNo("Y"); // true
yesNo("yes"); // true
yesNo("No"); // false
yesNo("Foo", true); // true