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Elixir Cross Referencer

# $NetBSD: cond-cmp-numeric-ge.mk,v 1.2 2020/10/24 08:46:08 rillig Exp $
#
# Tests for numeric comparisons with the >= operator in .if conditions.

# When both sides are equal, the >= operator always yields true.
.if 1 >= 1
.else
.  error
.endif

# This comparison yields the same result, whether numeric or character-based.
.if 1 >= 2
.  error
.endif

.if 2 >= 1
.else
.  error
.endif

# If this comparison were character-based instead of numerical, the
# 5 would be >= 14 since its first digit is greater.
.if 5 >= 14
.  error
.endif

.if 14 >= 5
.else
.  error
.endif

# Scientific notation is supported, as per strtod.
.if 2e7 >= 1e8
.  error
.endif

.if 1e8 >= 2e7
.else
.  error
.endif

# Floating pointer numbers can be compared as well.
# This might be tempting to use for version numbers, but there are a few pitfalls.
.if 3.141 >= 111.222
.  error
.endif

.if 111.222 >= 3.141
.else
.  error
.endif

# When parsed as a version number, 3.30 is greater than 3.7.
# Since make parses numbers as plain numbers, that leads to wrong results.
# Numeric comparisons are not suited for comparing version number.
.if 3.30 >= 3.7
.  error
.endif

.if 3.7 >= 3.30
.else
.  error
.endif

# As of 2020-08-23, numeric comparison is implemented as parsing both sides
# as double, and then performing a normal comparison.  The range of double is
# typically 16 or 17 significant digits, therefore these two numbers seem to
# be equal.
.if 1.000000000000000001 >= 1.000000000000000002
.else
.  error
.endif

all:
	@:;