GNU make manual 翻译(五十八)

继续翻译

Variable Assignment                        
-------------------                        
                        
Variable definitions are parsed as follows:                        
                        
     IMMEDIATE = DEFERRED                        
     IMMEDIATE ?= DEFERRED                        
     IMMEDIATE := IMMEDIATE                        
     IMMEDIATE += DEFERRED or IMMEDIATE                        
                        
     define IMMEDIATE                        
       DEFERRED                        
     endef                        
                        
     define IMMEDIATE =                        
       DEFERRED                        
     endef                        
                        
     define IMMEDIATE ?=                        
       DEFERRED                        
     endef                        
                        
     define IMMEDIATE :=                        
       IMMEDIATE                        
     endef                        
                        
     define IMMEDIATE +=                        
       DEFERRED or IMMEDIATE                        
     endef                        
                        
   For the append operator, `+=', the right-hand side is considered 
immediate if the variable was previously set as a simple variable 
(`:='), and deferred otherwise.                        

变量定义被如下解析:

IMMEDIATE = DEFERRED
IMMEDIATE ?= DEFERRED
IMMEDIATE := IMMEDIATE
IMMEDIATE += DEFERRED or IMMEDIATE

define IMMEDIATE
DEFERRED
endef

define IMMEDIATE =
DEFERRED
endef

define IMMEDIATE ?=
DEFERRED
endef

define IMMEDIATE :=
IMMEDIATE
endef

define IMMEDIATE +=
DEFERRED or IMMEDIATE
endef

 

For the append operator, `+=', the right-hand side is considered
immediate if the variable was previously set as a simple variable
(`:='), and deferred otherwise.

对于连接符号 +=, 如果变量已经被定义为一个简单变量(:=),那么右手边就被认为是立即性的,

否则就是推迟性的。

 

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posted @ 2012-09-17 10:36  健哥的数据花园  阅读(215)  评论(0编辑  收藏  举报