【已解决】Makefile中如何判断一个字符串变量存在另外一个字符串或列表中

折腾：

【已解决】更新gitbook发布脚本Makefile忽略某些book

期间，接着需要想办法如何从字符串获取到列表

或者去判断，某个字符串 是否在 一个字符串中

deploy_ignore_book_crifan_com.txt

test_book_name_1
scientific_network_summary
test_book_name_2

然后希望拿到一个变量是scientific_network_summary

能够判断，是否在上述的字符串中

makefile check contain string

Makefile : contains string – Stack Overflow

findstring

貌似就够用了？

GNU-make check if element exists in list/array – Stack Overflow

说是用filter

GNU make: Text Functions

“$(findstring find,in)

Searches in for an occurrence of find. If it occurs, the value is find; otherwise, the value is empty. You can use this function in a conditional to test for the presence of a specific substring in a given string. Thus, the two examples,

$(findstring a,a b c)

$(findstring a,b c)

produce the values ‘a’ and ‘’ (the empty string), respectively. See Testing Flags, for a practical application of findstring.

$(filter pattern…,text)

Returns all whitespace-separated words in text that do match any of the pattern words, removing any words that do not match. The patterns are written using ‘%’, just like the patterns used in the patsubst function above.

The filter function can be used to separate out different types of strings (such as file names) in a variable. For example:

sources := foo.c bar.c baz.s ugh.h

foo: $(sources)

        cc $(filter %.c %.s,$(sources)) -o foo

says that foo depends of foo.c, bar.c, baz.s and ugh.h but only foo.c, bar.c and baz.s should be specified in the command to the compiler.”

突然发现：findstring

不适合此处，此处的in是要一个list才行

How to check whether a variable contains spaces in a Makefile ? – Stack Overflow

先去试试再说

$(info IGNORE_FILE_CONTENT=$(IGNORE_FILE_CONTENT))
$(info BOOK_NAME=$(BOOK_NAME))
FOUND_BOOK = $(findstring $(BOOK_NAME), $(IGNORE_FILE_CONTENT))
$(info FOUND_BOOK=$(FOUND_BOOK))

是可以找到的：

IGNORE_FILE_CONTENT=test_book_name_1 scientific_network_summary test_book_name_2
BOOK_NAME=scientific_network_summary
FOUND_BOOK=scientific_network_summary

后续继续去判断是否为空

【已解决】Makefile中判断变量是否为空无效

【总结】

最后用：

FOUND_BOOK := $(findstring $(BOOK_NAME), $(IGNORE_FILE_CONTENT))

实现了，去判断

BOOK_NAME=scientific_network_summary

的确是在：

IGNORE_FILE_CONTENT

的值是：

scientific_network_summary

能够找到，并返回

scientific_network_summary

否则就返回Empty=None=null=空

注意不是空字符串。

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