From 24e9e9de7f0467386b61b27319e28e40454e9616 Mon Sep 17 00:00:00 2001
From: Mikael Vejdemo-Johansson <michiexile@gmail.com>
Date: Wed, 8 Apr 2015 15:29:32 +0200
Subject: [PATCH] support naming of generating functions, and 0-weighting of
symbols
---
examples/explore_singular.c | 152 ------------------------------------
examples/ties.c | 52 ++++++++++--
2 files changed, 45 insertions(+), 159 deletions(-)
delete mode 100644 examples/explore_singular.c
diff --git a/examples/explore_singular.c b/examples/explore_singular.c
deleted file mode 100644
index 5127c7c4..00000000
--- a/examples/explore_singular.c
+++ /dev/null
@@ -1,152 +0,0 @@
-//
-// Created by Mikael Vejdemo Johansson on 4/7/15.
-//
-// Intention: read in a parser, generate the system of equations for its
-// generating functions
-//
-
-#include <inttypes.h>
-#include "../src/backends/contextfree.h"
-#include "../src/backends/lr.h"
-#include <stdio.h>
-
-static const char *nonterminal_name(const HCFGrammar *g, const HCFChoice *nt)
-{
- static char buf[16] = {0}; // 14 characters in base 26 are enough for 64 bits
-
- // find nt's number in g
- size_t n = (uintptr_t)h_hashtable_get(g->nts, nt);
-
- // NB the start symbol (number 0) is always "A".
- int i;
- for(i=14; i>=0 && (n>0 || i==14); i--) {
- buf[i] = 'A' + n%26;
- n = n/26; // shift one digit
- }
-
- return buf+i+1;
-}
-
-
-
-void readsequence(FILE *file, uint32_t *count, uint32_t *length,
- const HCFGrammar *g, const HCFSequence *seq) {
- // tally up numbers of choices, and lengths of emitted strings.
- // Immediately emit any nonterminals encountered.
- HCFChoice** x = seq->items;
-
- if (*x == NULL) {
- return;
- } else {
- fprintf(file, "1");
- HCharset cs;
- unsigned int i, cscount=0;
- for(; *x; x++) {
- switch((*x)->type) {
- case HCF_CHAR:
- (*length)++;
- break;
- case HCF_END:
- break;
- case HCF_CHARSET:
- cs = (*x)->charset;
- for(i=0; i<256; i++) {
- if (charset_isset(cs, i)) {
- cscount++;
- }
- }
- *count *= cscount;
- break;
- default: // HCF_CHOICE, non-terminal symbol
- fprintf(file, "*%s(t)", nonterminal_name(g, *x));
- break;
- }
- }
- }
-}
-
-// For each nt in g->nts
-// For each choice in nt->key->seq
-// For all elements in sequence
-// Accumulate counts
-// Accumulate string lengths
-// Emit count*t^length
-void h_pprint_gfeqns(FILE *file, const HCFGrammar *g) {
- if (g->nts->used < 1) {
- return;
- }
-
- // determine maximum string length of symbol names
- int len;
- size_t s;
- for(len=1, s=26; s < g->nts->used; len++, s*=26);
-
- // iterate over g->nts
- size_t i;
- HHashTableEntry *hte;
- for(i=0; i < g->nts->capacity; i++) {
- for(hte = &g->nts->contents[i]; hte; hte = hte->next) {
- if (hte->key == NULL) {
- continue;
- }
-
- const HCFChoice *nt = hte->key;
- fprintf(file, "%s(t) = ", nonterminal_name(g, nt));
-
-
- for(HCFSequence **seq = nt->seq; *seq; seq++) {
- if (seq != nt->seq) {
- fprintf(file, " + ");
- }
- uint32_t count=1, length=0;
- readsequence(file, &count, &length, g, *seq);
- if(count == 1) {
- if(length == 1) {
- fprintf(file, "*t");
- }
- if(length > 1) {
- fprintf(file, "*t^%d", length);
- }
- } else if(count > 1) {
- if(length == 0) {
- fprintf(file, "*%d", count);
- }
- if(length == 1) {
- fprintf(file, "*%d*t", count);
- }
- if (length > 1) {
- fprintf(file, "*%d*t^%d", count, length);
- }
- }
- }
-
- fprintf(file, "\n");
- }
- }
-}
-
-
-
-
-int main(int argc, char **argv)
-{
- HAllocator *mm__ = &system_allocator;
-
- HParser *n = h_ch('n');
- HParser *E = h_indirect();
- HParser *T = h_choice(h_sequence(h_ch('('), E, h_ch(')'), NULL), n, NULL);
- HParser *E_ = h_choice(h_sequence(E, h_ch('-'), T, NULL), T, NULL);
- h_bind_indirect(E, E_);
- HParser *p = E;
-
- HCFGrammar *g = h_cfgrammar_(mm__, h_desugar_augmented(mm__, p));
- if (g == NULL) {
- fprintf(stderr, "h_cfgrammar failed\n");
- return 1;
- }
- printf("\n==== Generating functions ====\n");
- h_pprint_gfeqns(stdout, g);
-
- printf("\n==== Grammar ====\n");
- h_pprint_grammar(stdout, g, 0);
-}
diff --git a/examples/ties.c b/examples/ties.c
index e4ca2117..a379b5c7 100644
--- a/examples/ties.c
+++ b/examples/ties.c
@@ -10,8 +10,30 @@
#include "../src/backends/lr.h"
#include <stdio.h>
-static const char *nonterminal_name(const HCFGrammar *g, const HCFChoice *nt)
-{
+
+HAllocator *mm__;
+
+// If a parser has user_data set, the generating function systems will try
+// to interpret it as a string:
+//
+// If this string for an h_ch starts with the character 0, then that character
+// will have weight 0 in the generating function.
+//
+// Use the remaining string to set the preferred name of that parser in the
+// generating function.
+
+
+
+static const char *nonterminal_name(const HCFGrammar *g, const HCFChoice *nt) {
+ if(nt->user_data != NULL) {
+ if(*(char*)(nt->user_data) != '0') {
+ // user_data is a non-empty string
+ return nt->user_data;
+ } else {
+ return nt->user_data+1;
+ }
+ }
+
static char buf[16] = {0}; // 14 characters in base 26 are enough for 64 bits
// find nt's number in g
@@ -38,13 +60,16 @@ void readsequence(FILE *file, uint32_t *count, uint32_t *length,
if (*x == NULL) {
return;
} else {
+ char has_user_data = (*x)->user_data != NULL && *(char*)(*x)->user_data != 0;
fprintf(file, "1");
HCharset cs;
unsigned int i, cscount=0;
for(; *x; x++) {
switch((*x)->type) {
case HCF_CHAR:
- (*length)++;
+ if(!(has_user_data && *(char*)(*x)->user_data == '0')) {
+ (*length)++;
+ }
break;
case HCF_END:
break;
@@ -182,7 +207,21 @@ HParser* finkmaoTW() {
h_epsilon_p(),
NULL);
h_bind_indirect(pairstar, pstar_);
- return h_sequence(prefix, pairstar, tuck, NULL);
+
+ HParser* tie = h_sequence(prefix, pairstar, tuck, NULL);
+ h_desugar_augmented(mm__, tie);
+
+
+ T->desugared->user_data = "T";
+ W->desugared->user_data = "W";
+ U->desugared->user_data = "0U";
+ prefix->desugared->user_data = "prefix";
+ pair->desugared->user_data = "pair";
+ tuck->desugared->user_data = "tuck";
+ pstar_->desugared->user_data = "pairstar";
+ tie->desugared->user_data = "tie";
+
+ return tie;
}
HParser* depth1TW() {
@@ -341,9 +380,8 @@ HParser* depthNTW() {
}
-int main(int argc, char **argv)
-{
- HAllocator *mm__ = &system_allocator;
+int main(int argc, char **argv) {
+ mm__ = &system_allocator;
HParser *p = finkmaoTW();
HCFGrammar *g = h_cfgrammar_(mm__, h_desugar_augmented(mm__, p));
--
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