Source code of Windows XP (NT5)
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

122 lines
2.8 KiB

// Copyright (c) 1999 Microsoft Corporation. All rights reserved.
//
// Declaration of Lexer.
//
// Lexical analyzer for AudioVBScript. Breaks down the characters of source code into a stream tokens.
#pragma once
const int g_iMaxBuffer = 256; // max length for VBScript identifiers is 255
enum LexErr
{
LEXERR_NoError = 0,
LEXERR_InvalidCharacter,
LEXERR_NonAsciiCharacterInStringLiteral = LEXERR_InvalidCharacter,
LEXERR_IdentifierTooLong,
LEXERR_StringLiteralTooLong,
LEXERR_StringLiteralUnterminated,
LEXERR_NumericLiteralTooLarge,
LEXERR_Max
};
enum Token
{
TOKEN_eof = 0, // used for end of file or an error (nenzero error_num() indicates an error)
TOKEN_sub,
TOKEN_dim,
TOKEN_if,
TOKEN_then,
TOKEN_end,
TOKEN_elseif,
TOKEN_else,
TOKEN_set,
TOKEN_call,
TOKEN_lparen,
TOKEN_rparen,
TOKEN_comma,
TOKEN_op_minus,
TOKEN_op_not,
TOKEN_op_pow,
TOKEN_op_mult,
TOKEN_op_div,
TOKEN_op_mod,
TOKEN_op_plus,
TOKEN_op_lt,
TOKEN_op_leq,
TOKEN_op_gt,
TOKEN_op_geq,
TOKEN_op_eq,
TOKEN_op_neq,
TOKEN_is,
TOKEN_and,
TOKEN_or,
TOKEN_linebreak,
TOKEN_identifier,
TOKEN_identifierdot,
TOKEN_stringliteral,
TOKEN_numericliteral
};
struct TokenKeysym
{
WCHAR c;
Token t;
};
extern const TokenKeysym g_TokenKeysyms[];
struct TokenKeyword
{
const WCHAR *s;
Token t;
};
extern const TokenKeyword g_TokenKeywords[];
bool CheckOperatorType(Token t, bool fAcceptParens, bool fAcceptUnary, bool fAcceptBinary, bool fAcceptOverloadedAssignmentTokens);
class Lexer
{
public:
Lexer(const WCHAR *pwszSource);
Lexer &operator++() { Next(); Scan(); return *this; }
int line() { return m_iLine; }
int column() { return m_iColumn; }
operator Token() { return m_t; }
// Additional token-specific info. Only valid while on this token.
// error
int error_num() { assert(m_t == TOKEN_eof); return num(); } // 0 if no error
const char *error_descr() { assert(m_t == TOKEN_eof); return str(); }
// identifier and identifierdot
const char *identifier_name() { assert(m_t == TOKEN_identifier || m_t == TOKEN_identifierdot); return str(); }
// numeric literal
int numericliteral_val() { assert(m_t == TOKEN_numericliteral); return num(); }
// string literal
const char *stringliteral_text() { assert(m_t == TOKEN_stringliteral); return str(); }
private:
friend class CActiveScriptError;
void Next();
void Scan(); // handling for line break tokens and calls ScanMain
void ScanMain();
const char *str() { return m_szStr; } // Multipurpose string info set by some tokens.
void err(LexErr iErr);
int num() { return m_iNum; } // Multipurpose numeric info set by some tokens.
const WCHAR *m_p;
const WCHAR *m_pNext; // If this is set then the next Next call will advance the pointer (and the column) to this point.
int m_iLine;
int m_iColumn;
Token m_t;
char m_szStr[g_iMaxBuffer];
int m_iNum;
};