Update docs

doc/MOYimplJOY.md

@@ -54,27 +54,6 @@ _MSC_VER
 Special instructions on behalf of the Microsoft C compiler are guarded by these
 defines.
 
-REMEMBER_FILENAME
------------------
-
-In error reporting, the filename is not mentioned. The line where an error
-occurred is shown, followed by a line that contains a `^`, followed by an
-error message. That is presumably enough. But in case of many more files
-in the future, it might become necessary to mention the filename where the
-error occurred. That is when this define will be needed. This define can now
-be used, because file and line are reported when this define is enabled.
-
-SIGNAL_HANDLING
----------------
-
-If `gc.c` is used instead of the BDW garbage collector, this define offers the
-possibility to catch a segment violation and print a user-selected error
-message. The use of this feature is not recommended, because it prevents during
-debugging to pinpoint the exact location where the error occurred. Also `gc.c`
-is not recommended, as it is slower than the BDW garbage collector and the
-extra dependency is overcome by building from source by the Microsoft compiler
-or installing the BDW package in other environments.
-
 JVERSION
 --------
 
@@ -84,49 +63,6 @@ happens to be always 1.0 and whether it is a Release build or not can be seen
 by executing `ccmake .`. That program reads the latest CMakeCache.txt and
 reports about the options available therein.
 
-BDW_GARBAGE_COLLECTOR
----------------------
-
-The BDW garbage collector creates an extra dependency, but if it can be
-installed system wide, it is easy enough to link against it. It is faster than
-`gc.c`. The interface is kept the same, except that initialization was
-different. The `gc.c` needs to know what the top of the stack is, that is why
-it receives the address of argc through a global variable.
-
-CORRECT_INTERN_LOOKUP
----------------------
-
-This is a check that was originally not present in Joy. The check makes sure
-that a name that is interned constitutes a valid identifier. If not, printing
-the name may look very odd. In a colored version of Joy that could be remedied
-by giving symbols their own color, but as it is, it may be better to prevent
-illegal names.
-
-SEARCH_EXEC_DIRECTORY
----------------------
-
-This is an extension that allows sloppy locations of `usrlib.joy` and other
-libraries. The aim is to make library files available without copying them to
-a host of other directories. The original only looks in the current working
-directory. That may prevent out-of-source builds in CMake.
-
-USE_SNPRINTF
-------------
-
-Snprintf calculates the size of the buffer that is needed by printf. It makes
-the use of printf safer. The downside is that snprintf is not available in the
-ANSI standard. Even so, it might be beneficial to use this define when snprintf
-is available.
-
-WIN32
------
-
-Static analyzers point to various flaws in the source code, such as the use of
-`gmtime` and `localtime`, that should be replaced by `_r` functions. Ok, but
-the new functions are not available on the Windows platform. That is why this
-define is there. Maybe it should be replaced by a USE_R_FUNCTIONS define.
-This define is no longer needed.
-
 SOURCE_DATE_EPOCH
 -----------------
 
@@ -147,12 +83,6 @@ YYDEBUG
 When activated, this define allows the user to see the parse tree, as
 maintained by bison. A `-y` command flag is also required.
 
-COSMO
------
-
-Compiling against the cosmopolitan library seems attractive, but the
-combination of cosmopolitan and the BDW garbage collector may be difficult.
-
 ALARM
 -----
 
@@ -193,15 +123,15 @@ remaining option, -h, cannot be disabled.
 Implementation details
 ======================
 
-About the implementation: the aim is to not disturb the language. That means
-that all tests in the test2 directory and all examples in the lib directory
-should behave exactly as in the reference implementation of Joy.
+About the implementation: the aim is to leave the language untouched. That
+means that all tests in the test2 directory and all examples in the lib
+directory should behave exactly as in the reference implementation of Joy.
 
 What is different in this implementation is the use of vectors instead of
-linked lists and the absence of recursion. There are exceptions: `get` and
+linked lists and the stackless recursion. There are exceptions: `get` and
 `fget` use readfactor that may call readterm, that calls readfactor.
 
-The big advantage of not using recursion is in the size of data structures that
+The big advantage of stackless recursion is in the size of data structures that
 can be handled. A program that builds a list of integers looks like this:
 
     echo '1 100000 from-to-list.' | build/joy.exe
@@ -212,12 +142,18 @@ collector that causes the stack overflow. `Joy` has Cheney's algorithm
 implemented, that is not recursive but still fails because `from-to-list` makes
 use of `linrec` and `linrec` recurses.
 
-This implementation does not use recursion and so succeeds where other
-implementations fail. There is also a downside: function calling is slower.
+This implementation is stackless and so succeeds where other implementations
+fail. There is also a downside: function calling is slower.
+
+Benchmark
+---------
 
-Summary
-=======
+Implementation|fib (time)|lst (size)
+---|---|---
+42minjoy|1m12|
+joy0|38|13395
+Joy|1m25|43052
+joy1|3m37|72883
+Moy|2m3|10000000
 
-Linked lists are not good engineering. Recursion is not good engineering.
-Dynamic memory is not good engineering. Ok, this implementation uses dynamic
-memory. Lots of it.
+Moy is after all not the slowest implementation.

lib/numlib.joy

@@ -10,14 +10,11 @@ LIBRA
     even == 2 rem null;
     odd == even not;
     prime ==
-	[dup 2 =]
-	[pop true]
-	[2
-	[over over dup * > ord 2 pick 2 pick rem and]
-	[succ]
+	2
+	[ over over dup * > ord 2 pick 2 pick rem and ]
+	[ succ ]
 	while
-#	dup * < ;
-	rem null not] ifte;
+	dup * < ;
 
 (* functions *)
 

main.c

@@ -1,7 +1,7 @@
 /*
  *  module  : main.c
- *  version : 1.14
- *  date    : 09/11/23
+ *  version : 1.16
+ *  date    : 09/14/23
  */
 #include "globals.h"
 
@@ -135,7 +135,7 @@ PRIVATE void options(void)
     printf("  -v : do not print a copyright notice\n");
 #endif
 #ifdef OVERWRITE
-    printf("  -w : suppress warnings about overwriting builtin\n");
+    printf("  -w : suppress warnings: overwriting, arities\n");
 #endif
 #if YYDEBUG
     printf("  -y : print a trace of parser execution\n");
@@ -259,8 +259,7 @@ PRIVATE int my_main(int argc, char **argv)
     env.undeferror = INIUNDEFERROR;
     inilinebuffer(env.filename);
     inisymboltable(&env);
-    if (setjmp(begin) == SIGSEGV) /* return here after error or abort */
-	quit_(&env); /* do not continue after SIGSEGV */
+    setjmp(begin); /* return here after error or abort */
     lst_resize(env.prog, 0);
     if (mustinclude) {
 	mustinclude = include(&env, "usrlib.joy", ERROR_ON_USRLIB);
@@ -273,7 +272,6 @@ int main(int argc, char **argv)
 {
     int (*volatile m)(int, char **) = my_main;
 
-    signal(SIGSEGV, abortexecution_);
     GC_INIT();
     return (*m)(argc, argv);
 }

save.c

@@ -1,7 +1,7 @@
 /*
     module  : save.c
-    version : 1.5
-    date    : 09/07/23
+    version : 1.6
+    date    : 09/14/23
 */
 #include "globals.h"
 #include "prim.h"
@@ -21,9 +21,11 @@ PUBLIC void save(pEnv env, NodeList *list, int num)
         status = arity(env, list, num) == 1 ? ARITY_OK : ARITY_KNOWN;
     if (status == ARITY_KNOWN) {
 #ifdef ARITY
-        printf("arity: ");
-        writeterm(env, list, stdout);
-        printf("\n");
+	if (env->overwrite) {
+            printf("arity: ");
+            writeterm(env, list, stdout);
+            printf("\n");
+	}
 #endif
         status = ARITY_NOT_OK;
     }

src/minus.c

@@ -1,7 +1,7 @@
 /*
     module  : minus.c
-    version : 1.4
-    date    : 09/11/23
+    version : 1.5
+    date    : 09/14/23
 */
 #ifndef MINUS_C
 #define MINUS_C
@@ -15,11 +15,34 @@ void minus_(pEnv env)
 {
 #ifndef COMPILER
     Node first, second;
+#ifdef USE_BIGNUM_ARITHMETIC
+    int sign1, sign2;
+    int64_t num, num1, num2;
+#endif
 
     PARM(2, PLUSMINUS);
     second = lst_pop(env->stck);
     first = lst_pop(env->stck);
     switch (first.op) {
+#ifdef USE_BIGNUM_ARITHMETIC
+    case BIGNUM_:
+	switch (second.op) {
+	case BIGNUM_:
+	    first.u.str = num_str_sub(first.u.str, second.u.str);
+	    break;
+
+	case FLOAT_:
+	    second.u.str = dbl2big(second.u.dbl);
+	    first.u.str = num_str_sub(first.u.str, second.u.str);
+	    break;
+
+	default:
+	    second.u.str = num2big(second.u.num);
+	    first.u.str = num_str_sub(first.u.str, second.u.str);
+	    break;
+	}
+	break;
+#endif
     case FLOAT_:
 	switch (second.op) {
 	case FLOAT_:
@@ -34,13 +57,37 @@ void minus_(pEnv env)
 
     default:
 	switch (second.op) {
+#ifdef USE_BIGNUM_ARITHMETIC
+	case BIGNUM_:
+	    first.u.str = dbl2big(first.u.dbl);
+	    first.u.str = num_str_sub(first.u.str, second.u.str);
+	    first.op = BIGNUM_;
+	    break;
+#endif
 	case FLOAT_:
 	    second.u.dbl = first.u.num - second.u.dbl;
 	    lst_push(env->stck, second);
 	    return;
 
 	default:
-	    first.u.num -= second.u.num;
+#ifdef USE_BIGNUM_ARITHMETIC
+	    num1 = first.u.num;
+	    num2 = second.u.num;
+	    sign1 = num1 < 0;
+	    sign2 = num2 < 0;
+	    if (!sign1 && sign2) { /* overflow possible */
+		num2 = -num2;
+		num = num1 + num2; /* unsigned addition, possible wrap around */
+		if (num < num1 || num < num2) { /* test overflow */
+		    first.u.str = num2big(num1);
+		    second.u.str = num2big(num2);
+		    first.u.str = num_str_add(first.u.str, second.u.str);
+		    first.op = BIGNUM_;
+		} else
+		    first.u.num += num2;
+	    } else
+#endif
+		first.u.num -= second.u.num;
 	    break;
 	}
 	break;

src/plus.c

@@ -1,7 +1,7 @@
 /*
     module  : plus.c
-    version : 1.6
-    date    : 09/11/23
+    version : 1.7
+    date    : 09/14/23
 */
 #ifndef PLUS_C
 #define PLUS_C
@@ -88,7 +88,7 @@ void plus_(pEnv env)
 		    num1 = -num1;
 		    num2 = -num2;
 		}
-		num = num1 + num2;
+		num = num1 + num2; /* unsigned addition, possible wrap around */
 		if (num < num1 || num < num2) { /* test overflow */
 		    first.u.str = num2big(num1);
 		    second.u.str = num2big(num2);

undo.c

@@ -1,7 +1,7 @@
 /*
     module  : undo.c
-    version : 1.5
-    date    : 09/07/23
+    version : 1.6
+    date    : 09/14/23
 */
 #include "globals.h"
 #include "prim.h"
@@ -21,9 +21,11 @@ PUBLIC void undo(pEnv env, NodeList *list, int num)
         status = arity(env, list, num) == 1 ? ARITY_OK : ARITY_KNOWN;
     if (status == ARITY_KNOWN) {
 #ifdef ARITY
-        printf("arity: ");
-        writeterm(env, list, stdout);
-        printf("\n");
+	if (env->overwrite) {
+            printf("arity: ");
+            writeterm(env, list, stdout);
+            printf("\n");
+	}
 #endif
         status = ARITY_NOT_OK;
     }