diff options
author | John Ankarström <john@ankarstrom.se> | 2022-07-15 13:13:50 +0200 |
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committer | John Ankarström <john@ankarstrom.se> | 2022-07-15 13:13:50 +0200 |
commit | 8f1ead168558dac9cf4c10e269f568e15b5f8faf (patch) | |
tree | b749f5abfa5720f491a56740f61f6de00b9e0bfc /c | |
parent | 9d5ee7f8bd62f11cb0d9019cc4a715f265452bb7 (diff) | |
download | EpisodeBrowser-8f1ead168558dac9cf4c10e269f568e15b5f8faf.tar.gz |
Add support for Prolog exceptions.
Diffstat (limited to 'c')
-rw-r--r-- | c/common.cpp | 3 | ||||
-rw-r--r-- | c/defs.h | 41 | ||||
-rw-r--r-- | c/pl.cpp | 39 |
3 files changed, 74 insertions, 9 deletions
diff --git a/c/common.cpp b/c/common.cpp index 89cc426..dd84742 100644 --- a/c/common.cpp +++ b/c/common.cpp @@ -31,7 +31,8 @@ TCHAR *TszFromSz(const char *sz, int iCp) Library::Library(const TCHAR *tszLibrary) { - if (!(m_hModule = LoadLibrary(tszLibrary))) + m_hModule = LoadLibrary(tszLibrary); + if (!m_hModule) throw std::invalid_argument("Library not found."); } @@ -66,8 +66,19 @@ struct DataListView : public ListView }; /* pl.cpp */ -int Pl(const char *, const char *); +int Plx(const char *, const char *); +struct Query +{ + Query(module_t ctx, predicate_t p, term_t t0); + ~Query(); + int Cut(); + int Close(); + int NextSolution(); +private: + qid_t m_q; +}; +/* Polymorphic aliases for PL_put_*, PL_get_*. */ inline int PlPut(term_t t, int x) { return PL_put_integer(t, x); } inline int PlPut(term_t t, long x) { return PL_put_integer(t, x); } inline int PlPut(term_t t, long long x) { return PL_put_integer(t, x); } @@ -92,6 +103,7 @@ inline int PlGet(term_t t, long long *x) { return PL_get_int64(t, x); } inline int PlGet(term_t t, atom_t *x) { return PL_get_atom(t, x); } inline int PlGet(term_t t, char **x) { return PL_get_atom_chars(t, x); } +/* Helper templates for Plx, Pl. */ template <typename T> int PlPutv(term_t t, T arg) { return PlPut(t, arg); } template <typename T, typename ...R> @@ -104,18 +116,39 @@ template <typename T> int Countv(int i, T arg) { return i+1; } template <typename T, typename ...R> int Countv(int i, T arg, R... rest) { return Countv(i+1, rest...); } + +/* Call Prolog predicate, propagating Prolog exceptions. */ template <typename ...T> -int Pl(const char *szMod, const char *szPred, T... args) +int Plx(const char *szMod, const char *szPred, T... args) { int iArity = Countv(0, args...); term_t t = PL_new_term_refs(iArity); if (!PlPutv(t, args...)) return 0; - if (!PL_call_predicate(NULL, PL_Q_CATCH_EXCEPTION, PL_predicate(szPred, iArity, szMod), t)) - return 0; + Query q(NULL, PL_predicate(szPred, iArity, szMod), t); + if (!q.NextSolution()) return 0; if (!PlGetv(t, args...)) return 0; return 1; } +/* Call Prolog predicate, ignoring Prolog exceptions. */ +inline int Pl(const char *szMod, const char *szPred) +{ + try { + return Plx(szMod, szPred); + } catch (term_t &t) { + return 0; + } +} +template <typename ...T> +int Pl(const char *szMod, const char *szPred, T... args) +{ + try { + return Plx(szMod, szPred, args...); + } catch (term_t &t) { + return 0; + } +} + /* defs.h */ #ifdef UNICODE #define WA "W" @@ -1,9 +1,40 @@ #include <SWI-Prolog.h> +#include "defs.h" -int Pl(const char *szMod, const char *szPred) +Query::Query(module_t ctx, predicate_t p, term_t t0) +{ + m_q = PL_open_query(ctx, PL_Q_CATCH_EXCEPTION, p, t0); +} + +Query::~Query() +{ + PL_cut_query(m_q); +} + +int Query::Cut() +{ + if (PL_cut_query(m_q)) return 1; + if (term_t t = PL_exception(m_q)) throw t; + return 0; +} + +int Query::Close() +{ + if (PL_close_query(m_q)) return 1; + if (term_t t = PL_exception(m_q)) throw t; + return 0; +} + +int Query::NextSolution() +{ + if (PL_next_solution(m_q)) return 1; + if (term_t t = PL_exception(m_q)) throw t; + return 0; +} + +int Plx(const char *szMod, const char *szPred) { term_t t = PL_new_term_refs(0); - if (!PL_call_predicate(NULL, PL_Q_CATCH_EXCEPTION, PL_predicate(szPred, 0, szMod), t)) - return 0; - return 1; + Query q(NULL, PL_predicate(szPred, 0, szMod), t); + return q.NextSolution(); } |