func newLexer(nm string, sz int, r io.RuneReader, report *xc.Report) (*lexer, error) {
file := xc.FileSet.AddFile(nm, -1, sz+2)
lx, err := lex.New(
file,
r,
lex.ErrorFunc(func(pos token.Pos, msg string) {
report.Err(pos, msg)
}),
lex.RuneClass(func(r rune) int { return int(r) }),
)
if err != nil {
return nil, err
}
l := &lexer{
Lexer: lx,
report: report,
}
l.emit(&Call{Target: 2})
l.emit(&Halt{})
l.enter = &Enter{NVars: -1}
l.jmp = &Jmp{Target: -1}
l.emit(l.enter)
l.emit(l.jmp)
return l, nil
}
// Bind attempts to bind the name in t to node. Errors are reported to report.
func (b *Bindings) Bind(t xc.Token, node Node, report *xc.Report) {
nm := t.Val
if x := b.Map[nm]; x != nil {
ok := false
switch e := x.Node.(type) {
case *ConstSpec, *Variable:
case *ProcSpec:
ok = e == nil
default:
panic("internal error")
}
if !ok {
report.ErrTok(t, "redeclaration of %s at %s", xc.Dict.S(nm), position(x.Pos))
return
}
}
b.Map[nm] = &Binding{node, t.Pos()}
}