Inserting special characters

After pressing the alt-I key, one or more characters (space separated if necessary) can be entered using any of the following notations for special characters:

^X for ctrl-X: This is written as a two character combination: the ^ character followed by a letter from A to Z (in upper or lower case).
DDD for a decimal value: Any combinations of digits 0 to 9 is replaced by a character with the corresponding code.
\xHHH or 0xHHH or U+HHH for a hexadecimal value: A two character prefix followed by a hex number is replaced by a character with the corresponding code. These three prefixes are based on various standards (e.g U+ for Unicode code point) and all have the same meaning in CLEX.

Null code character cannot be inserted. CLEX does not check if the code is valid in the current encoding. WARNING: Inserting characters with invalid codes might have undesired effects.

Examples:

^C - ctrl-C, ASCII code 3
98 - letter b - ASCII code 98
\x62 - letter b as above
U+3c8 - greek letter ψ (psi) (Unicode only)