bazel build //my_folder/my_subfolder:node_modules 中的 //（双正斜杠）和 :（冒号）是什么意思？

Question

I do not understand this syntax:

bazel build //<my_dir>/<my_subdir>:node_modules

I believe // is to specify a route relative to a WORKSPACE, but the meaning of : is unclear to me.

Similarly, you can use bazel build ... and that seems to build all subfolders within a WORSKPACE.

What are all these strange symbols? Where are they documented?

Answer 1

The documentation for this is here: https://docs.bazel.build/versions/master/build-ref.html

Additional syntax related to external dependencies is documented here: https://docs.bazel.build/versions/master/external.html

Things like ... are called target patterns and are documented here: https://docs.bazel.build/versions/master/guide.html#target-patterns

I believe // is to specify a route relative to a WORKSPACE

Correct, // starts an "absolute label"

meaning of :

This separates the package (on the left) from the target name in the package (on the right).

you can use bazel build ... and that seems to build all subfolders within a WORSKPACE

That will build all targets in the current package (ie, current working directory) and subpackages of the current package. If you're at the root of the workspace, then it's the same as //... which will build everything.