Hello,
Perhaps I am misunderstanding the purpose or do not know how to optimally
use this package, but the way I see it scanner.peek() is not doing what I
expect it to do: return the next non-whitespace token (e.g., scanner.Ident,
scanner.Int etc) without advancing the scanner. Instead it returns whatever
is the next rune in the stream (which could be a space or any other char).
So, as far as I could tell, there is no easy way to lookahead and switch
the call to scanner.Scan on the kind of the next token. This complicates
writing generic syntax checking functions like:
//TODO: handle error better
accept := func(wantedTok rune, wantedText string) {
tok = s.Scan()
log.Printf("%s: %d %s\n", s.Pos(), tok, s.TokenText())
if tok != wantedTok {
log.Fatalf("Syntax error at position %s. Expected %d. Found %d",
s.Pos(), wantedTok, tok)
}
if wantedText != "" && wantedText != s.TokenText() { //case-sensitive?
log.Fatalf("Syntax error at position %s. Expected %s. Found %s",
s.Pos(), wantedText, s.TokenText())
}
}
Should not scanner.Peek do whatever scanner.Scan does just without
advancing the scanner?
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