[question] toolchains: generate in a list of scopes?

[SpaceIm]

• I've read the CONTRIBUTING guide.

Sorry if I already asked, but in high level toolchains helpers, is it possible to call generate() method of these helpers with a list of scopes?

In boost recipe I would need to create a custom scope which has everything from build scope except one toolchain, so that onespecific self.run afterwards during build() is called with this custom scope, but all other self.run of build() should be executed with build scope. See conan-io/conan-center-index#14415 (comment)

In conan v1, it was quite easy to have fine-grained env vars for each self.run. But with conan v2 paradigm where all vars are supposed to be written in one or several scripts in generate() and associated to scope names, so that they can be called afterwards, it's less obvious.

Current generate() of boost recipe in conan-io/conan-center-index#14415 is quite simple:

    def generate(self):
        if not self.options.header_only:
            env = VirtualBuildEnv(self)
            env.generate()
            if is_msvc(self):
                vc = VCVars(self)
                vc.generate()

But would it be possible to have something like this (pretty sure it doesn't work currently since scope argument expects a string):

    def generate(self):
        if not self.options.header_only:
            env = VirtualBuildEnv(self)
            env.generate(scope=["build", "build_but_without_vc_vars_when_b2_is_called"])
            if is_msvc(self):
                vc = VCVars(self)
                vc.generate()