Function: downcase

downcase is a function defined in casefiddle.c.

Signature

(downcase OBJ)

Documentation

Convert argument to lower case and return that.

The argument may be a character or string. The result has the same type, including the multibyteness of the string.

This means that if this function is called with a unibyte string argument, and downcasing it would turn it into a multibyte string
(according to the current locale), the downcasing is done using ASCII
"C" rules instead. To accurately downcase according to the current
locale, the string must be converted into multibyte first.

The argument object is not altered--the value is a copy.

Other relevant functions are documented in the string group.

View in manual

Probably introduced at or before Emacs version 29.1.

Shortdoc

;; string
(downcase "FOObar")
    => "foobar"

Source Code

// Defined in /usr/src/emacs/src/casefiddle.c
{
  return casify_object (CASE_DOWN, obj);
}