Begin working on an initial implementation for the parser.

This commit is contained in:
Danila Fedorin 2018-02-10 22:40:34 -08:00
parent 6d836a5513
commit 0958ecd1eb
2 changed files with 55 additions and 1 deletions

View File

@ -9,7 +9,9 @@ enum libab_result {
LIBAB_SUCCESS, LIBAB_SUCCESS,
LIBAB_MALLOC, LIBAB_MALLOC,
LIBAB_BAD_PATTERN, LIBAB_BAD_PATTERN,
LIBAB_FAILED_MATCH LIBAB_FAILED_MATCH,
LIBAB_EOF,
LIBAB_UNEXPECTED
}; };
typedef enum libab_result libab_result; typedef enum libab_result libab_result;

View File

@ -1,3 +1,9 @@
#include "libabacus.h"
#include "parser.h"
#include "libabacus_util.h"
#include "lexer.h"
#include <stdlib.h>
struct parser_state { struct parser_state {
ll_node* current_node; ll_node* current_node;
lexer_match* current_match; lexer_match* current_match;
@ -20,10 +26,56 @@ void _parser_state_step(struct parser_state* state) {
} }
_parser_state_update(state); _parser_state_update(state);
} }
int _parser_is_char(struct parser_state* state, char to_expect) {
return (state->current_match && state->current_match->type == TOKEN_CHAR &&
state->string[state->current_match->from] == to_expect);
}
int _parser_eof(struct parser_state* state) {
return state->current_match == NULL;
}
libab_result _parser_consume_char(struct parser_state* state, char to_consume) {
libab_result result = LIBAB_SUCCESS;
if(state->current_match == NULL) {
result = LIBAB_EOF;
} else if(state->current_match->type != TOKEN_CHAR ||
state->string[state->current_match->from] != to_consume) {
result = LIBAB_UNEXPECTED;
} else {
_parser_state_step(state);
}
return result;
}
libab_result _parse_block(struct parser_state* state,
tree** store_into, int expect_braces) {
libab_result result = LIBAB_SUCCESS;
*store_into = malloc(sizeof(**store_into));
if(*store_into == NULL) result = LIBAB_MALLOC;
if(expect_braces && result == LIBAB_SUCCESS) result = _parser_consume_char(state, '{');
while(result == LIBAB_SUCCESS &&
!_parser_eof(state) &&
!(expect_braces && _parser_is_char(state, '}'))) {
}
if(expect_braces && result == LIBAB_SUCCESS) result = _parser_consume_char(state, '}');
return result;
}
libab_result parse_tokens(ll* tokens, const char* string, tree** store_into) { libab_result parse_tokens(ll* tokens, const char* string, tree** store_into) {
libab_result result = LIBAB_SUCCESS; libab_result result = LIBAB_SUCCESS;
struct parser_state state; struct parser_state state;
_parser_state_init(&state, tokens, string); _parser_state_init(&state, tokens, string);
result = _parse_block(&state, store_into, 0);
if(result == LIBAB_SUCCESS) {
(*store_into)->variant = BASE;
}
return result; return result;
} }