Add catcherr() built-in function.

contrib/remind-conf-mode/remind-conf-mode.el

@@ -164,7 +164,7 @@
 (defconst remind-builtin-functions
   (sort
    (list "_" "abs" "access" "adawn" "adusk" "ampm" "ansicolor" "args" "asc"
-         "baseyr" "catch" "char" "choose" "coerce" "columns" "current" "date"
+         "baseyr" "catch" "catcherr" "char" "choose" "coerce" "columns" "current" "date"
          "datepart" "datetime" "dawn" "day" "daysinmon" "defined" "dosubst"
          "dusk" "easterdate" "escape" "evaltrig" "filedate" "filedatetime"
          "filedir" "filename" "getenv" "hebdate" "hebday" "hebmon" "hebyear"

man/remind.1.in

@@ -3288,6 +3288,29 @@ Note in the last example that catch does \fInot\fR protect you from errors
 in the evaluation of \fBarg2\fR.
 .RE
 .TP
+.B catcherr()
+Returns a string representing the error message from the most
+recently-evaluated \fBcatch()\fR function whose first argument yielded
+an error.  Note that the error message is always in English even if
+\fBRemind\fR has been localized; this lets you reliably test the return
+value.  Here are some examples:
+.RS
+.PP
+.nf
+    # No "catch" invocations yet:  sets a to "Ok"
+    set a catcherr()
+
+    # Sets b to "oops" and a to "Division by zero"
+    set b catch(1/0, "oops")
+    set a catcherr()
+
+    # Sets b to 1 and a to "Division by zero".  The catch error
+    # is never cleared by a non-error catch()
+    set b catch(4-3, "not-evaluated")
+    set a catcherr()
+.fi
+.RE
+.TP
 .B char(i_i1 [,i_i2...])
 This function can take any number of \fBINT\fR arguments.  It returns
 a \fBSTRING\fR consisting of the bytes specified by the arguments.

src/funcs.c

@@ -64,6 +64,9 @@
 #define PUT(x) DBufPuts(&DebugBuf, x)
 #define OUT() do { fprintf(ErrFp, "%s\n", DBufValue(&DebugBuf)); DBufFree(&DebugBuf); } while(0)
 
+/* Last error from catch() */
+static int LastCatchError = OK;
+
 static int
 solstice_equinox_for_year(int y, int which);
 
@@ -79,6 +82,7 @@ static int FArgs           (func_info *);
 static int FAsc            (func_info *);
 static int FBaseyr         (func_info *);
 static int FCatch          (expr_node *, Value *, Value *, int *);
+static int FCatchErr       (func_info *);
 static int FChar           (func_info *);
 static int FChoose         (expr_node *, Value *, Value *, int *);
 static int FCoerce         (func_info *);
@@ -245,6 +249,7 @@ BuiltinFunc Func[] = {
     {   "asc",          1,      1,      1,          FAsc, NULL },
     {   "baseyr",       0,      0,      1,          FBaseyr, NULL },
     {   "catch",        2,      2,      1,          NULL, FCatch }, /* NEW-STYLE */
+    {   "catcherr",     0,      0,      0,          FCatchErr, NULL },
     {   "char",         1,      NO_MAX, 1,          FChar, NULL },
     {   "choose",       2,      NO_MAX, 1,          NULL, FChoose }, /*NEW-STYLE*/
     {   "coerce",       2,      2,      1,          FCoerce, NULL },
@@ -1320,6 +1325,9 @@ static int FCatch(expr_node *node, Value *locals, Value *ans, int *nonconst)
         }
         return r;
     }
+
+    /* Save the catch error */
+    LastCatchError = r;
     if (DebugFlag & DB_PRTEXPR) {
         PUT("*");
         PUT(GetErr(r));
@@ -1344,6 +1352,19 @@ static int FCatch(expr_node *node, Value *locals, Value *ans, int *nonconst)
     }
     return r;
 }
+
+/***************************************************************/
+/*                                                             */
+/*  FCatchErr                                                  */
+/*  Return (as a string) the English error thrown by the last  */
+/*  catch() expression that errored out.                       */
+/*                                                             */
+/***************************************************************/
+static int FCatchErr(func_info *info)
+{
+    return RetStrVal(GetEnglishErr(LastCatchError), info);
+}
+
 /***************************************************************/
 /*                                                             */
 /*  FChoose                                                    */

src/main.c

@@ -2138,6 +2138,14 @@ int GetOnceDate(void)
     return OnceDate;
 }
 
+char const *GetEnglishErr(int r)
+{
+    if (r < 0 || r >= NumErrs) {
+        r = E_SWERR;
+    }
+    return ErrMsg[r];
+}
+
 char const *GetErr(int r)
 {
     char const *msg;

src/protos.h

@@ -271,6 +271,7 @@ void InitTranslationTable(void);
 char const *GetTranslatedString(char const *orig);
 int GetTranslatedStringTryingVariants(char const *orig, DynamicBuffer *out);
 char const *GetErr(int r);
+char const *GetEnglishErr(int r);
 char const *tr(char const *s);
 void print_escaped_string(FILE *fp, char const *s);
 void print_escaped_string_helper(FILE *fp, char const *s, int esc_for_remind, int json);

tests/test.cmp

@@ -16256,27 +16256,39 @@ D'oh, a file whose name has spaces! ../tests/with space.rem
 
 DEBUG +x
 # Test catch() built-in function
+set m catcherr()
+catcherr() => "Ok"
 set a catch(4/2, 33)
 4 / 2 => 2
 catch(2, ?) => 2
+set m catcherr()
+catcherr() => "Ok"
 set a catch(4/0, 33)
 4 / 0 => Division by zero
 catch(*Division by zero*, 33) => 33
+set m catcherr()
+catcherr() => "Division by zero"
 set a catch(4/0, 1/0)
 4 / 0 => Division by zero
 1 / 0 => Division by zero
-../tests/test.rem(1444): `/': Division by zero
+../tests/test.rem(1447): `/': Division by zero
 catch(*Division by zero*, *Division by zero*) => Division by zero
+set m catcherr()
+catcherr() => "Division by zero"
 set a catch(catch(4/0, 1/0), 39)
 4 / 0 => Division by zero
 1 / 0 => Division by zero
 catch(*Division by zero*, *Division by zero*) => Division by zero
 catch(*Division by zero*, 39) => 39
+set m catcherr()
+catcherr() => "Division by zero"
 set a catch(4/0, catch(4/0, 39))
 4 / 0 => Division by zero
 4 / 0 => Division by zero
 catch(*Division by zero*, 39) => 39
 catch(*Division by zero*, 39) => 39
+set m catcherr()
+catcherr() => "Division by zero"
 set a catch(1/0, catch("f" * "g", catch($IntMin*88, 42)))
 1 / 0 => Division by zero
 "f" * "g" => Type mismatch
@@ -16285,10 +16297,12 @@ $IntMin => -2147483648
 catch(*Number too high*, 42) => 42
 catch(*Type mismatch*, 42) => 42
 catch(*Division by zero*, 42) => 42
+set m catcherr()
+catcherr() => "Number too high"
 DEBUG -x
 DEBUG -e
 Variable hash table statistics:
-  Entries: 100141; Buckets: 87719; Non-empty Buckets: 66299
+  Entries: 100142; Buckets: 87719; Non-empty Buckets: 66300
   Maxlen: 5; Minlen: 0; Avglen: 1.142; Stddev: 0.878; Avg nonempty len: 1.510
   Growths: 13; Shrinks: 0
 Function hash table statistics:
@@ -24110,6 +24124,7 @@ args
 asc
 baseyr
 catch
+catcherr
 char
 choose
 coerce

tests/test.rem

@@ -1439,12 +1439,19 @@ do "with space.rem"
 
 DEBUG +x
 # Test catch() built-in function
+set m catcherr()
 set a catch(4/2, 33)
+set m catcherr()
 set a catch(4/0, 33)
+set m catcherr()
 set a catch(4/0, 1/0)
+set m catcherr()
 set a catch(catch(4/0, 1/0), 39)
+set m catcherr()
 set a catch(4/0, catch(4/0, 39))
+set m catcherr()
 set a catch(1/0, catch("f" * "g", catch($IntMin*88, 42)))
+set m catcherr()
 DEBUG -x
 DEBUG -e