resolve: a non-binding use of a global may precede its binding #123
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According to the agreed Skylark spec, and unlike the Python semantics currently implemented, this program should yield a dynamic error: print(len) # dynamic error: uninitialized global len = 1 print(len) We now defer the resolution of forward-uses at top level until the end of the module, just as we do for locals. Fixes #116 Change-Id: I802bded5d50c45702a4da08c40144574cdf4296a
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| @@ -1140,6 +1140,7 @@ nested in any order, to any depth. | |||
| If name is bound anywhere within a block, all uses of the name within | |||
| the block are treated as references to that binding, even uses that | |||
| appear before the binding. | |||
| This is true even in the module block, unlike Python. | |||
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Why continue to maintain this document instead of pointing to https://docs.bazel.build/versions/master/skylark/spec.html? There should be one true spec.
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This document accurately describes the language implemented by Skylark-in-Go. A single true spec would be nice, but for the Bazel team, support for uses of Skylark other than Bazel does not appear to be a priority right now, so Skylark-in-Java lags behind some features that we agreed upon such as support for the kinds of numbers encountered in protocol buffers, separation of x.f() calls into two steps y = x.f; y(), the string methods elem_ords, codepoints, and codepoint_ords, and so on.
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My recommendation is to point to https://github.com/bazelbuild/starlark/blob/master/spec.md
and document only the differences. Hopefully we can reduce the list of differences over time.
This change causes the AllowGlobalReassign flag (used for legacy Bazel semantics) to also allow use of predeclared names prior to a global binding of the same name, as in: print(len); len=1; print(len) This effectively reverses github.com/google/skylark/pull/123 behind an option. See github.com/google/skylark/issues/116 for discussion. Change-Id: If514136aaa705154379f445e3b1b287fcb1fdfd6
This change causes the AllowGlobalReassign flag (used for legacy Bazel semantics) to also allow use of predeclared names prior to a global binding of the same name, as in: print(len); len=1; print(len) This effectively reverses github.com/google/skylark/pull/123 behind an option. See github.com/google/skylark/issues/116 for discussion.
According to the agreed Skylark spec, and unlike the Python semantics currently implemented, this program should yield a dynamic error:
We now defer the resolution of forward-uses at top level until the end of the module, just as we do for locals.
Fixes #116