.\" $OpenBSD: string.in,v 1.4 2019/02/06 20:54:28 schwarze Exp $
.TH STRING 1 "February 6, 2019"
.SH NAME
string \- conditional testing whether a string is defined
.SH DESCRIPTION
.ie d mystr OOPS
.el mystr not yet defined
.br
.ds mystr mystrval
.ie d mystr now defined
.el OOPS
.if !d mystr OOPS
.PP
.ie d mymac OOPS
.el mymac not yet defined
.br
.de mymac
mymacval
..
.ie dmymac now defined
.el OOPS
.if !d  mymac OOPS
.PP
.ie d myren OOPS
.el myren not yet defined
.br
.rn SM myren
.ie d myren now defined
.el OOPS
.if !d myren OOPS
.PP
standard macro is
.ie d PP defined
.el not defined \(em OOPS
.PP
identifier and tab:
.ie d mystr	mystr is defined
.el OOPS
.PP
escape sequence after identifier:
.ie d mystr\(enmystr is defined
.el OOPS