cpp5.l

来自「用于lex和yacc的c++及c语言的文法,可用来构造C++语言的编译器」· L 代码 · 共 372 行 · 第 1/2 页

octal_escape  [0-7]{1,3}
hex_escape "x"[0-9a-fA-F]+

escape_sequence [\\]({simple_escape}|{octal_escape}|{hex_escape})
c_char [^'\\\n]|{escape_sequence}
s_char [^"\\\n]|{escape_sequence}


h_tab [\011]
form_feed [\014]
v_tab [\013]
c_return [\015]

horizontal_white [ ]|{h_tab}



%%


{horizontal_white}+     {
			WHITE_RETURN(' ');
			}

({v_tab}|{c_return}|{form_feed})+   {
			WHITE_RETURN(' ');
			}


({horizontal_white}|{v_tab}|{c_return}|{form_feed})*"\n"   {
			NEW_LINE_RETURN();
			}

auto                {PA_KEYWORD_RETURN(AUTO);}
break               {PA_KEYWORD_RETURN(BREAK);}
case                {PA_KEYWORD_RETURN(CASE);}
char                {PA_KEYWORD_RETURN(CHAR);}
const               {PA_KEYWORD_RETURN(CONST);}
continue            {PA_KEYWORD_RETURN(CONTINUE);}
default             {PA_KEYWORD_RETURN(DEFAULT);}
define             {PP_KEYWORD_RETURN(DEFINE);}
defined            {PP_KEYWORD_RETURN(OPDEFINED);}
do                  {PA_KEYWORD_RETURN(DO);}
double              {PA_KEYWORD_RETURN(DOUBLE);}
elif                {PP_KEYWORD_RETURN(ELIF);}
else              {PPPA_KEYWORD_RETURN(ELSE);}
endif              {PP_KEYWORD_RETURN(ENDIF);}
enum                {PA_KEYWORD_RETURN(ENUM);}
error              {PP_KEYWORD_RETURN(ERROR);}
extern              {PA_KEYWORD_RETURN(EXTERN);}
float               {PA_KEYWORD_RETURN(FLOAT);}
for                 {PA_KEYWORD_RETURN(FOR);}
goto                {PA_KEYWORD_RETURN(GOTO);}
if                {PPPA_KEYWORD_RETURN(IF);}
ifdef              {PP_KEYWORD_RETURN(IFDEF);}
ifndef             {PP_KEYWORD_RETURN(IFNDEF);}
include            {PP_KEYWORD_RETURN(INCLUDE); }
int                 {PA_KEYWORD_RETURN(INT);}
line               {PP_KEYWORD_RETURN(LINE);}
long                {PA_KEYWORD_RETURN(LONG);}
pragma             {PP_KEYWORD_RETURN(PRAGMA);}
register            {PA_KEYWORD_RETURN(REGISTER);}
return              {PA_KEYWORD_RETURN(RETURN);}
short               {PA_KEYWORD_RETURN(SHORT);}
signed              {PA_KEYWORD_RETURN(SIGNED);}
sizeof              {PA_KEYWORD_RETURN(SIZEOF);}
static              {PA_KEYWORD_RETURN(STATIC);}
struct              {PA_KEYWORD_RETURN(STRUCT);}
switch              {PA_KEYWORD_RETURN(SWITCH);}
typedef             {PA_KEYWORD_RETURN(TYPEDEF);}
undef              {PP_KEYWORD_RETURN(UNDEF);}
union               {PA_KEYWORD_RETURN(UNION);}
unsigned            {PA_KEYWORD_RETURN(UNSIGNED);}
void                {PA_KEYWORD_RETURN(VOID);}
volatile            {PA_KEYWORD_RETURN(VOLATILE);}
while               {PA_KEYWORD_RETURN(WHILE);}


class               {CPP_KEYWORD_RETURN(CLASS);}
delete              {CPP_KEYWORD_RETURN(DELETE);}
friend              {CPP_KEYWORD_RETURN(FRIEND);}
inline              {CPP_KEYWORD_RETURN(INLINE);}
new                 {CPP_KEYWORD_RETURN(NEW);}
operator            {CPP_KEYWORD_RETURN(OPERATOR);}
overload            {CPP_KEYWORD_RETURN(OVERLOAD);}
protected           {CPP_KEYWORD_RETURN(PROTECTED);}
private             {CPP_KEYWORD_RETURN(PRIVATE);}
public              {CPP_KEYWORD_RETURN(PUBLIC);}
this                {CPP_KEYWORD_RETURN(THIS);}
virtual             {CPP_KEYWORD_RETURN(VIRTUAL);}

{identifier}          {IDENTIFIER_RETURN();}

{decimal_constant}  {NUMERICAL_RETURN(INTEGERconstant);}
{octal_constant}    {NUMERICAL_RETURN(OCTALconstant);}
{hex_constant}      {NUMERICAL_RETURN(HEXconstant);}
{floating_constant} {NUMERICAL_RETURN(FLOATINGconstant);}


"L"?[']{c_char}+[']     {
			NUMERICAL_RETURN(CHARACTERconstant);
			}


"L"?["]{s_char}*["]     {
			LITERAL_RETURN(STRINGliteral);}




"("                  {PPOP_RETURN(LP);}
")"                  {PPOP_RETURN(RP);}
","                  {PPOP_RETURN(COMMA);}
"#"                  {NAMED_PPOP_RETURN('#') ;}
"##"                 {NAMED_PPOP_RETURN(POUNDPOUND);}

"{"                  {ASCIIOP_RETURN(LC);}
"}"                  {ASCIIOP_RETURN(RC);}
"["                  {ASCIIOP_RETURN(LB);}
"]"                  {ASCIIOP_RETURN(RB);}
"."                  {ASCIIOP_RETURN(DOT);}
"&"                  {ASCIIOP_RETURN(AND);}
"*"                  {ASCIIOP_RETURN(STAR);}
"+"                  {ASCIIOP_RETURN(PLUS);}
"-"                  {ASCIIOP_RETURN(MINUS);}
"~"                  {ASCIIOP_RETURN(NEGATE);}
"!"                  {ASCIIOP_RETURN(NOT);}
"/"                  {ASCIIOP_RETURN(DIV);}
"%"                  {ASCIIOP_RETURN(MOD);}
"<"                  {ASCIIOP_RETURN(LT);}
">"                  {ASCIIOP_RETURN(GT);}
"^"                  {ASCIIOP_RETURN(XOR);}
"|"                  {ASCIIOP_RETURN(PIPE);}
"?"                  {ASCIIOP_RETURN(QUESTION);}
":"                  {ASCIIOP_RETURN(COLON);}
";"                  {ASCIIOP_RETURN(SEMICOLON);}
"="                  {ASCIIOP_RETURN(ASSIGN);}

".*"                 {NAMEDOP_RETURN(DOTstar);}
"::"                 {NAMEDOP_RETURN(CLCL);}
"->"                 {NAMEDOP_RETURN(ARROW);}
"->*"                {NAMEDOP_RETURN(ARROWstar);}
"++"                 {NAMEDOP_RETURN(ICR);}
"--"                 {NAMEDOP_RETURN(DECR);}
"<<"                 {NAMEDOP_RETURN(LS);}
">>"                 {NAMEDOP_RETURN(RS);}
"<="                 {NAMEDOP_RETURN(LE);}
">="                 {NAMEDOP_RETURN(GE);}
"=="                 {NAMEDOP_RETURN(EQ);}
"!="                 {NAMEDOP_RETURN(NE);}
"&&"                 {NAMEDOP_RETURN(ANDAND);}
"||"                 {NAMEDOP_RETURN(OROR);}
"*="                 {NAMEDOP_RETURN(MULTassign);}
"/="                 {NAMEDOP_RETURN(DIVassign);}
"%="                 {NAMEDOP_RETURN(MODassign);}
"+="                 {NAMEDOP_RETURN(PLUSassign);}
"-="                 {NAMEDOP_RETURN(MINUSassign);}
"<<="                {NAMEDOP_RETURN(LSassign);}
">>="                {NAMEDOP_RETURN(RSassign);}
"&="                 {NAMEDOP_RETURN(ANDassign);}
"^="                 {NAMEDOP_RETURN(ERassign);}
"|="                 {NAMEDOP_RETURN(ORassign);}
"..."                {NAMEDOP_RETURN(ELLIPSIS);}



%%

/* I won't bother to provide any error recovery. I won't  even  handle
unknown characters */

/*******************************************************************/
int isaTYPE(string)
char * string;
{
    /*  We  should  really  be  maintaining  a  symbol  table,  and be
    carefully keeping track of what the current scope is  (or  in  the
    case  of  "rescoped"  stuff,  what  scope  to  look in). Since the
    grammar is not annotated with  actions  to  track  transitions  to
    various  scopes,  and  there  is no symbol table, we will supply a
    hack to allow folks to test  the  grammar  out.   THIS  IS  NOT  A
    COMPLETE IMPLEMENTATION!!!! */

    return ('A' <= string[0] && 'Z' >= string[0]);
}