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/*
* @LANG: c++
*/
#include <iostream>
using namespace std;
struct LangEl
{
int key;
const char *name;
};
struct Fsm
{
int cs;
// Initialize the machine. Invokes any init statement blocks. Returns 0
// if the machine begins in a non-accepting state and 1 if the machine
// begins in an accepting state.
int init( );
// Execute the machine on a block of data. Returns -1 if after processing
// the data, the machine is in the error state and can never accept, 0 if
// the machine is in a non-accepting state and 1 if the machine is in an
// accepting state.
int execute( LangEl *data, int len );
// Indicate that there is no more data. Returns -1 if the machine finishes
// in the error state and does not accept, 0 if the machine finishes
// in any other non-accepting state and 1 if the machine finishes in an
// accepting state.
int finish( );
};
%%{
machine Fsm;
alphtype int;
getkey fpc->key;
variable eof eof_marker;
action a1 {}
action a2 {}
action a3 {}
main := ( 1 2* 3 )
${cout << fpc->name << endl;}
%/{cout << "accept" << endl;};
}%%
%% write data;
int Fsm::init( )
{
%% write init;
return 0;
}
int Fsm::execute( LangEl *data, int len )
{
LangEl *p = data;
LangEl *pe = data + len;
LangEl *eof_marker = pe;
%% write exec;
if ( cs == Fsm_error )
return -1;
if ( cs >= Fsm_first_final )
return 1;
return 0;
}
int Fsm::finish( )
{
if ( cs == Fsm_error )
return -1;
if ( cs >= Fsm_first_final )
return 1;
return 0;
}
int main( )
{
static Fsm fsm;
static LangEl lel[] = {
{1, "one"},
{2, "two-a"},
{2, "two-b"},
{2, "two-c"},
{3, "three"}
};
fsm.init();
fsm.execute( lel, 5 );
fsm.finish();
return 0;
}
#ifdef _____OUTPUT_____
one
two-a
two-b
two-c
three
accept
#endif
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