tree d9b665bc0affc706523a7ad1144cb7420e1f9a57
parent 6118004e0db99820f1b6eb15d7901987c1f5481f
author Googler <noreply@google.com> 1568561977 -0700
committer Copybara-Service <copybara-worker@google.com> 1568562031 -0700

bazel syntax: simplify comprehensions

This change merges {List,Dict,Abstract}Comprehension into a
single concrete class. The "k: v" body in a dict comprehension
{k: v for vars in iterable} is now represented as
DictionaryLiteral.Entry.

"Clause" was a poor abstraction: clients need to know that
there are only two instances, If and For, and handle them
specifically.

The doEval method is now a single recursive
function that fits easily in a single page.

We delete the following classes:

  AbstractBuilder
  OutputCollector
  ListComprehension
    Builder
    ListOutputCollector
  Clause.Kind
  DictComprehension
    Builder
    DictOutputCollector

PiperOrigin-RevId: 269185401