69 lines
1.9 KiB
C
69 lines
1.9 KiB
C
#include "parser_internal.h"
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typedef struct {
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const HParser *p;
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HPredicate pred;
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} HAttrBool;
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static HParseResult* parse_attr_bool(void *env, HParseState *state) {
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HAttrBool *a = (HAttrBool*)env;
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HParseResult *res = h_do_parse(a->p, state);
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if (res && res->ast) {
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if (a->pred(res))
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return res;
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else
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return NULL;
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} else
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return NULL;
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}
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static bool ab_isValidRegular(void *env) {
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HAttrBool *ab = (HAttrBool*)env;
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return ab->p->vtable->isValidRegular(ab->p->env);
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}
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/* Strictly speaking, this does not adhere to the definition of context-free.
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However, for the purpose of making it easier to handle weird constraints on
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fields, we've decided to allow boolean attribute validation at parse time
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for now. We might change our minds later. */
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static bool ab_isValidCF(void *env) {
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HAttrBool *ab = (HAttrBool*)env;
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return ab->p->vtable->isValidCF(ab->p->env);
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}
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static HCFChoice* desugar_ab(HAllocator *mm__, void *env) {
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HAttrBool *a = (HAttrBool*)env;
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HCFSequence *seq = h_new(HCFSequence, 1);
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seq->items = h_new(HCFChoice*, 2);
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seq->items[0] = h_desugar(mm__, a->p);
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seq->items[1] = NULL;
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HCFChoice *ret = h_new(HCFChoice, 1);
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ret->type = HCF_CHOICE;
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ret->seq = h_new(HCFSequence*, 2);
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ret->seq[0] = seq;
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ret->seq[1] = NULL;
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ret->pred = a->pred;
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return ret;
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}
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static const HParserVtable attr_bool_vt = {
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.parse = parse_attr_bool,
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.isValidRegular = ab_isValidRegular,
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.isValidCF = ab_isValidCF,
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.desugar = desugar_ab,
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};
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const HParser* h_attr_bool(const HParser* p, HPredicate pred) {
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return h_attr_bool__m(&system_allocator, p, pred);
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}
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const HParser* h_attr_bool__m(HAllocator* mm__, const HParser* p, HPredicate pred) {
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HParser *res = h_new(HParser, 1);
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res->vtable = &attr_bool_vt;
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HAttrBool *env = h_new(HAttrBool, 1);
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env->p = p;
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env->pred = pred;
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res->env = (void*)env;
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return res;
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}
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