filter
$(filter word1 word2,$(VARIANTS))
判断变量VARIANTS中是否包含word1和 word2,如果包含就把VARIANTS中包含的word1和word2之外的过滤掉
示例:
VARIANTS := mon tue wed thu fri sat sun
DAY := $(filter sat sun,$(VARIANTS))
$(info $(DAY))
输出结果为:
sat sun
filter-out
$(filter-out word1 word2,$(VARIANTS))
判断变量VARIANTS中是否包含word1和 word2,如果包含就把VARIANTS中包含的word1和word2过滤掉,其余的全部保留
示例:
VARIANTS := mon tue wed thu fri sat sun
DAY := $(filter-out sat sun,$(VARIANTS))
$(info $(DAY))
输出结果为:
mon tue wed thu fri
mon tue wed thu fri