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#pragma once
#include <istream>
#include <string>
#include <cstdint>
#include <deque>
namespace cps {
enum Token {
tok_eof = -1,
tok_declare = -2,
tok_integer_kw = -3,
tok_input = -4,
tok_output = -5,
tok_constant = -43,
tok_case = -40,
tok_endcase = -41,
tok_otherwise = -42,
tok_if = -6,
tok_then = -7,
tok_else = -8,
tok_endif = -9,
tok_while = -10,
tok_endwhile = -12,
tok_repeat = -13,
tok_until = -14,
tok_for = -15,
tok_to = -16,
tok_step = -17,
tok_next = -18,
tok_array = -19,
tok_of = -20,
tok_real_kw = -21,
tok_boolean_kw = -22,
tok_true = -23,
tok_false = -24,
tok_and = -25,
tok_or = -26,
tok_not = -27,
tok_string_kw = -30,
tok_string_literal = -36,
tok_char_kw = -38,
tok_char_literal = -39,
tok_identifier = -100,
tok_number_int = -101,
tok_number_real = -102,
tok_assign = -200, // <-
tok_eq = -201, // =
tok_ne = -202, // <>
tok_le = -203, // <=
tok_ge = -204, // >=
tok_div = -205,
tok_mod = -206,
tok_colon = -300, // :
tok_operator = -398,
tok_overload = -399,
tok_function = -400,
tok_endfunction = -401,
tok_return = -402,
tok_returns = -403,
tok_procedure = -404,
tok_endprocedure = -405,
tok_call = -406,
tok_byref = -407,
tok_byval = -408,
tok_openfile = -500,
tok_readfile = -501,
tok_writefile = -502,
tok_closefile = -503,
tok_read = -504,
tok_write = -505,
tok_append = -506,
tok_random = -507,
tok_type = -600,
tok_endtype = -601,
tok_set = -602, // reserved: SET types are recognised but not implemented
tok_define = -603, // reserved: DEFINE (set literals) likewise
tok_class = -604,
tok_endclass = -605,
tok_public = -606,
tok_private = -607,
tok_c_type = -608,
tok_c_int = -609,
tok_c_char = -610,
tok_c_string = -611,
tok_c_double = -612,
tok_new = -613, tok_delete = -614,
tok_include = -650, tok_global = -651, tok_endglobal = -652,
tok_include_obj = -653, tok_extern = -654,
tok_extern_function = -655, tok_extern_procedure = -656,
tok_ellipsis = -657, // ...
tok_try = -700,
tok_catch = -701,
tok_endtry = -702,
tok_throw = -703
};
class Lexer {
std::istream &Input;
int LastChar = ' ';
int CurrentLine = 1;
int TokenLine = 1;
bool HadError = false;
bool Library = false;
bool LineStart = true;
struct TokenData {
int Kind, Line;
std::string Identifier, String;
uint64_t Integer;
double Real;
char Character;
};
std::deque<TokenData> Lookahead;
std::string readEscape(bool IsChar);
int readToken();
TokenData captureToken(int Kind) const;
void restoreToken(const TokenData &Token);
public:
explicit Lexer(std::istream &Input) : Input(Input) {}
std::string IdentifierStr;
std::string StringVal;
uint64_t NumVal = 0;
double RealVal = 0;
char CharVal = '\0';
int gettok();
int peekToken(unsigned Offset = 0);
int peekLine(unsigned Offset = 0);
int getLine() const { return TokenLine; }
bool isLibrary() const { return Library; }
bool hadError() const { return HadError; }
};
}
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