RE: = or := for asignment?

[Paul Smith]

On Wed, 2012-03-07 at 05:15 -0800, Mark Galeck (CW) wrote:
> "Immediate" means, the value is assigned as soon as make sees the
> assignment.  That is :=  
> 
> "Deferred" means, the assignment is noted but the value is not
> assigned until it is necessary to do so later.  That is =

These statements are slightly misleading.  A value is _assigned_ to a
variable when make reads the assignment line, regardless of whether you
use = or :=.

The difference (as described in the manual) is when the value is
_expanded_.  In a deferred assignment (=) the value is not expanded
until sometime later, when the variable is used in an immediate context.

In an immediate assignment (:=) the value is expanded before it is
assigned (and then not expanded again when the variable is used).

See if the manual's description is helpful.

Cheers!

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