.ie

.ie [!]condition anything
.el anything

If portion of if-else. If condition is true, do anything. Otherwise do anything following .el request. .ie/.el pairs can be nested. Syntax for condition is described under .if.

Example

If first argument isn't 2, columns are 1.8 inches wide; otherwise, columns are 2.5 inches wide:

.ie !'\\$1'2' .MC 1.8i 0.2i
.el .MC 2.5i 0.25i