Update Go scanner to accept non-ASCII operators

Read the discussion of this change on the golang-nuts mailing list. See this notice in UTF-8 format.

For each line, the scanner accepts, in place of the first operator, any of the remaining operators, and outputs a token whose string (set in $GOROOT/src/go/token/token.go) is the first operator.

! ¬

!= ≠

& ∧

&& ⋀

&= ∧=

&^ ∧¬

&^= ∧¬=

… …

:= ≔

<- ←

<< ≪

<<= ≪=

<= ≤

== =? ≟

>= ≥

>> ≫

>>= ≫=

^ ⊻

^= ⊻=

| ∨

|= ∨=

|| ⋁

To install, copy $GOROOT/src/pkg/go/scanner/scanner.go to another file.

Replace scanner.go with scanner.go

Run $GOROOT/src/all.bash and check for 0 unexpected errors.

Changes to scanner.go update gofmt, which accepts UTF-8 operators and outputs their ASCII equivalents.  This mkfile production rule uses gofmt as a preprocessor to create a sharable and compilable file.

%.go: %.ℊℴ

cat $stem.ℊℴ | gofmt > $stem.go

See these files for an example of each new operator form in the context of a simple Go program.

myscanner.ℊℴ

chan.ℊℴ

Please mail me privately if something doesn’t work with this code, to avoid noise on the golang-nuts list, since we’re no longer discussing officially-released code.