Unicode Input - Character Mnemonics

Character Mnemonics

RFC 1345 defines a large number (1,893) of suggested mnemonics for code points in Unicode 1.0 (as well as characters in ISO 2DIS 10646 and many other character sets in use at the time of publication). Although the document does not restrict the length of a mnemonic (for example, "10000R" for U+2821), most (1,338) of the mnemonics are two characters long, and most (416) of the remaining are three-characters. While never complete, and targeting obsolescent set definitions, the mnemonics themselves can still be used.

• Vim allows mnemonics entry (confusingly called "digraphs" by Vim developers) in insert mode (the regular mode for typing text) with Ctrl+K followed by a two-keystroke RFC 1345 mnemonic; or, in addition, if the digraph option is set, by entering the first character followed by a backspace followed by the second character. Custom mnemonics can also be defined for arbitrary code points. (For example, "dig Gr 9881" associates "Gr" with U+2699 ⚙ gear.)

• GNU Emacs allows mnemonics entry by switching to rfc1345 input mode (by default Ctrl+x Ctrl+\.

• GNU Screen allows mnemonics entry with (by default) Ctrl+A Ctrl+V.

• Zsh allows mnemonics entry using the insert-composed-char widget.

RFC 1345 predates the introduction of the Euro sign (€, U+20AC), but the above applications included it as the mnemonic "Eu".