Change `for` desugaring & make refutable pattern errors more precise#14444

Merged

bors merged 3 commits intorust-lang:masterfrom

huonw:nice-for-errors

May 27, 2014

Commits on May 26, 2014

syntax: Add a source field to `Local` for tracking if it comes from `let`s or `for`s.
huonw
committed
syntax: desugar a `for` loop to a let binding to get better error
huonw
committed
rustc: provide more precise information about refutable patterns.
huonw
committed