## Appendix C Digraphs ¶

C accepts aliases for certain characters. Apparently in the 1990s some computer systems had trouble inputting these characters, or trouble displaying them. These digraphs almost never appear in C programs nowadays, but we mention them for completeness.

‘`<:`’

  An alias for ‘`[`’.

‘`:>`’

  An alias for ‘`]`’.

‘`<%`’

  An alias for ‘`{`’.

‘`%>`’

  An alias for ‘`}`’.

‘`%:`’

  An alias for ‘`#`’, used for preprocessing directives (see Directives) and macros (see Macros).