8.1 M4 Quotation

The most common problem with existing macros is an improper quotation. This section, which users of Autoconf can skip, but which macro writers must read, first justifies the quotation scheme that was chosen for Autoconf and then ends with a rule of thumb. Understanding the former helps one to follow the latter.

8.1.1 Active Characters		Characters that change the behavior of M4
8.1.2 One Macro Call		Quotation and one macro call
8.1.3 Quotation and Nested Macros		Macros calling macros
8.1.4 changequote is Evil		Worse than INTERCAL: M4 + changequote
8.1.5 Quadrigraphs		Another way to escape special characters
8.1.6 Quotation Rule Of Thumb		One parenthesis, one quote