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Diffstat (limited to 'doc/man/scons.1')
| -rw-r--r-- | doc/man/scons.1 | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/doc/man/scons.1 b/doc/man/scons.1 index 08b62e2..441ef00 100644 --- a/doc/man/scons.1 +++ b/doc/man/scons.1 @@ -2987,6 +2987,7 @@ This function takes two arguments, an array of targets to be created by the function action, and an array of sources used to create the target(s): +.ES def build_it(target, source, env): # build the target from the source return 0 @@ -2994,7 +2995,40 @@ def build_it(target, source, env): def string_it(target, source): return "building '%s' from '%s'" % (target[0], source[0]) +# Use a positional argument. a = Action(build_it, string_it) + +# Alternatively, use a keyword argument. +a = Action(build_it, strfunction=string_it) +.EE + +The third, also optional argument +is a list of construction variables +whose values will be included +in the signature of the Action +when deciding whether a target should +be rebuilt because the action changed. +This is necessary whenever you want a target to +be rebuilt by an action when a specific +construction variable changes, +because the underlying Python code for a function +will not change when the value of the construction variable does. + +.ES +def build_it(target, source, env): + # build the target from the 'XXX' construction variable + open(target[0], 'w').write(env['XXX']) + return 0 + +def string_it(target, source): + return "building '%s' from '%s'" % (target[0], source[0]) + +# Use positional arguments. +a = Action(build_it, string_it, ['XXX']) + +# Alternatively, use a keyword argument. +a = Action(build_it, varlist=['XXX']) +.EE .PP If the action argument is not one of the above, None is returned. |