The presence or absence of whitespace is used to determine which
operator is in use, following the rules described in #520.
Support for prefix * dereference operator follows #523.
Co-authored-by: Geoff Romer <gromer@google.com>
Factor out code for pattern parsing, that only recognizes this form for
now, and uniformly form a 'PatternBinding' parse node for this, for
both variables and patterns.
This should clean up our top level directory and the build patterns.
No non-mechanical edits here. Just injecting `toolchain/` and
`TOOLCHAIN_` and then running formatting tools.
Richard SmithandGeoff Romer
Chandler Carruth