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Elixir Cross Referencer

# $NetBSD: cond-cmp-string.mk,v 1.11 2020/10/30 14:53:31 rillig Exp $
#
# Tests for string comparisons in .if conditions.

# This is a simple comparison of string literals.
# Nothing surprising here.
.if "str" != "str"
.  error
.endif

# The right-hand side of the comparison may be written without quotes.
.if "str" != str
.  error
.endif

# The left-hand side of the comparison must be enclosed in quotes.
# This one is not enclosed in quotes and thus generates an error message.
.if str != str
.  error
.endif

# The left-hand side of the comparison requires a defined variable.
# The variable named "" is not defined, but applying the :U modifier to it
# makes it "kind of defined" (see VAR_KEEP).  Therefore it is ok here.
.if ${:Ustr} != "str"
.  error
.endif

# Any character in a string literal may be escaped using a backslash.
# This means that "\n" does not mean a newline but a simple "n".
.if "string" != "\s\t\r\i\n\g"
.  error
.endif

# It is not possible to concatenate two string literals to form a single
# string.
.if "string" != "str""ing"
.  error
.endif

# There is no = operator for strings.
.if !("value" = "value")
.  error
.else
.  error
.endif

# There is no === operator for strings either.
.if !("value" === "value")
.  error
.else
.  error
.endif

# A variable expression can be enclosed in double quotes.
.if ${:Uword} != "${:Uword}"
.  error
.endif

# Between 2003-01-01 (maybe even earlier) and 2020-10-30, adding one of the
# characters " \t!=><" directly after a variable expression resulted in a
# "Malformed conditional", even though the string was well-formed.
.if ${:Uword } != "${:Uword} "
.  error
.endif
# Some other characters worked though, and some didn't.
# Those that are mentioned in is_separator didn't work.
.if ${:Uword0} != "${:Uword}0"
.  error
.endif
.if ${:Uword&} != "${:Uword}&"
.  error
.endif
.if ${:Uword!} != "${:Uword}!"
.  error
.endif
.if ${:Uword<} != "${:Uword}<"
.  error
.endif

# Adding another variable expression to the string literal works though.
.if ${:Uword} != "${:Uwo}${:Urd}"
.  error
.endif

# Adding a space at the beginning of the quoted variable expression works
# though.
.if ${:U word } != " ${:Uword} "
.  error
.endif