Method peek

chapter20/src/main/java/com/seaofnodes/simple/Parser.java:1446–1446

(char ch)

    private boolean matchOpx(char c0, char c1) { return _lexer.matchOpx(c0,c1);  }
    // Return true and do NOT skip if 'ch' is next
    private boolean peek(char ch) { return _lexer.peek(ch); }
    private boolean peekIsId() { return _lexer.peekIsId(); }

    // ch is +/- 1, means oper++ or oper-- means postfix