bazel - When to use predeclared outputs?

Question

I can declare that my rule creates a given file with:

zip = ctx.actions.declare_file("{}.zip".format(ctx.label.name))

However, the documentation also mentions that I can have predeclared output files but doesn't go into detail about them:

rule(
    implementation = ...,
    attrs = {
        ...
    },
    outputs = {
        "zip": "%{name}.zip", # accessible via ctx.outputs.zip
    },
)

What is the difference between predeclaring an output file vs doing it in the rule implementation and when should we use one or the other?

question from:https://stackoverflow.com/questions/66053299/when-to-use-predeclared-outputs

Answer 1

Waitting for answers