[Scons-users] SCons.Node.Python.Value on target_factory

[Gary Oberbrunner]

On Sun, Apr 7, 2013 at 9:42 PM, Philipp Kraus <philipp.kraus at flashpixx.de>wrote:


>

> Am 08.04.2013 um 03:11 schrieb Bill Deegan:

>

> Any reason your not just doing Execute(your_actions)?

> Are you using the dependencies? It looks like not.

> Unless I'm misunderstanding, you just want an alias to run some commands

> for you.

>

>

> The discussion goes off-topic, please forgot the previous discussion and

> take a look to this example only:

>

> ------------

> import SCons.Action

>

> env = Environment()

>

> env["BUILDERS"]["WithPyValue"]    = SCons.Builder.Builder( action =

> SCons.Action.Action("echo testbuild 1"),    source_factory =

> SCons.Node.FS.File, target_factory = SCons.Node.Python.Value )

> env["BUILDERS"]["WithoutPyValue"] = SCons.Builder.Builder( action =

> SCons.Action.Action("echo testbuild 2"), source_factory =

> SCons.Node.FS.File )

>

>

> env.WithPyValue("target1", "source1")

> # env.WithoutPyValue("target2", "source2")

> ---------------

>

>

> In this case my system produce:

>

> scons: Building targets ...

> scons: `.' is up to date.

> scons: done building targets.

>

> IMHO it should produce an error "source1" not exists, but in this case it

> should be the default target.

>

>

Probably you're not using the generated python value (returned by
WithPyValue) anywhere.  SCons by default builds all filesystem targets
under '.'. Your target (a Value) is not a file under . so SCons doesn't
think it needs to be built.

Try making it a dependency of something else:
  foo=env.WithPyValue(...)
  bar=env.Command(...)
  Depends(bar, foo)
or something like that.

But if you're making a source code builder, it may be instructive to learn
(as Bill says) that SCons has had one for a long time, it never worked that
well, and most people found it easier to just check out the source outside
of SCons or just Execute() the source code commands.

-- 
Gary
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://four.pairlist.net/pipermail/scons-users/attachments/20130408/b15fe9fd/attachment.htm>