Fix some code style, add tuple/type function.

We need to be able to detect tuple type from janet code, otherwise
tuples will contain hidden state. The tuple/type function is able
to detect the flags in the tuple so the programmer can access them
if needed.

src/core/compile.c

@@ -446,7 +446,6 @@ static JanetSlot janetc_tuple(JanetFopts opts, Janet x) {
             JOP_MAKE_TUPLE);
 }
 
-
 static JanetSlot janetc_tablector(JanetFopts opts, Janet x, int op) {
     JanetCompiler *c = opts.compiler;
     return janetc_maker(opts,
@@ -556,7 +555,7 @@ JanetSlot janetc_value(JanetFopts opts, Janet x) {
                     /* Empty tuple is tuple literal */
                     if (janet_tuple_length(tup) == 0) {
                         ret = janetc_cslot(x);
-		    } else if (janet_tuple_flag(tup) & JANET_TUPLE_FLAG_BRACKETCTOR) { // [] tuples are not function call
+                    } else if (janet_tuple_flag(tup) & JANET_TUPLE_FLAG_BRACKETCTOR) { /* [] tuples are not function call */
                         ret = janetc_tuple(opts, x);
                     } else {
                         JanetSlot head = janetc_value(subopts, tup[0]);

src/core/parse.c

@@ -335,22 +335,14 @@ static int comment(JanetParser *p, JanetParseState *state, uint8_t c) {
     return 1;
 }
 
-static Janet close_tuple(JanetParser *p, JanetParseState *state) {
+static Janet close_tuple(JanetParser *p, JanetParseState *state, int32_t flag) {
     Janet *ret = janet_tuple_begin(state->argn);
+    janet_tuple_flag(ret) = flag;
     for (int32_t i = state->argn - 1; i >= 0; i--)
         ret[i] = p->args[--p->argcount];
     return janet_wrap_tuple(janet_tuple_end(ret));
 }
 
-static Janet close_ltuple(JanetParser *p, JanetParseState *state) {
-    Janet *ret = janet_tuple_begin(state->argn);
-    janet_tuple_flag(ret) |= JANET_TUPLE_FLAG_BRACKETCTOR;
-    for (int32_t i = state->argn - 1; i >= 0; i--)
-        ret[i] = p->args[--p->argcount];
-    return janet_wrap_tuple(janet_tuple_end(ret));
-}
-
-
 static Janet close_array(JanetParser *p, JanetParseState *state) {
     JanetArray *array = janet_array(state->argn);
     for (int32_t i = state->argn - 1; i >= 0; i--)
@@ -495,11 +487,7 @@ static int root(JanetParser *p, JanetParseState *state, uint8_t c) {
                     if (state->flags & PFLAG_ATSYM) {
                         ds = close_array(p, state);
                     } else {
-		      if (c == ']') {
-			ds = close_ltuple(p, state);
-		      } else {
-                        ds = close_tuple(p, state);
-		      }
+                        ds = close_tuple(p, state, c == ']' ? JANET_TUPLE_FLAG_BRACKETCTOR : 0);
                     }
                 } else if (c == '}' && (state->flags & PFLAG_CURLYBRACKETS)) {
                     if (state->argn & 1) {

src/core/pp.c

@@ -332,16 +332,19 @@ static void janet_pretty_one(struct pretty *S, Janet x, int is_dict_value) {
         case JANET_ARRAY:
         case JANET_TUPLE:
             {
+                int32_t i, len;
+                const Janet *arr;
                 int isarray = janet_checktype(x, JANET_ARRAY);
-                janet_buffer_push_cstring(S->buffer, isarray ? "@[" : "(");
+                janet_indexed_view(x, &arr, &len);
+                int hasbrackets = !isarray && (janet_tuple_flag(arr) & JANET_TUPLE_FLAG_BRACKETCTOR);
+                const char *startstr = isarray ? "@[" : hasbrackets ? "[" : "(";
+                const char endchar = isarray ? ']' : hasbrackets ? ']' : ')';
+                janet_buffer_push_cstring(S->buffer, startstr);
                 S->depth--;
                 S->indent += 2;
                 if (S->depth == 0) {
                     janet_buffer_push_cstring(S->buffer, "...");
                 } else {
-                    int32_t i, len;
-                    const Janet *arr;
-                    janet_indexed_view(x, &arr, &len);
                     if (!isarray && len >= 5)
                         janet_buffer_push_u8(S->buffer, ' ');
                     if (is_dict_value && len >= 5) print_newline(S, 0);
@@ -352,7 +355,7 @@ static void janet_pretty_one(struct pretty *S, Janet x, int is_dict_value) {
                 }
                 S->indent -= 2;
                 S->depth++;
-                janet_buffer_push_u8(S->buffer, isarray ? ']' : ')');
+                janet_buffer_push_u8(S->buffer, endchar);
                 break;
             }
         case JANET_STRUCT:

src/core/tuple.c

@@ -120,6 +120,16 @@ static Janet cfun_tuple_append(int32_t argc, Janet *argv) {
     return janet_wrap_tuple(janet_tuple_end(n));
 }
 
+static Janet cfun_tuple_type(int32_t argc, Janet *argv) {
+    janet_fixarity(argc, 1);
+    const Janet *tup = janet_gettuple(argv, 0);
+    if (janet_tuple_flag(tup) & JANET_TUPLE_FLAG_BRACKETCTOR) {
+        return janet_ckeywordv("brackets");
+    } else {
+        return janet_ckeywordv("parens");
+    }
+}
+
 static const JanetReg tuple_cfuns[] = {
     {
         "tuple/slice", cfun_tuple_slice,
@@ -142,6 +152,15 @@ static const JanetReg tuple_cfuns[] = {
                 "returns a new tuple. Items are prepended such that the "
                 "last element in items is the first element in the new tuple.")
     },
+    {
+        "tuple/type", cfun_tuple_type,
+        JDOC("(tuple/type tup)\n\n"
+                "Checks how the tuple was constructed. Will return the keyword "
+                ":brackets if the tuple was parsed with brackets, and :parens "
+                "otherwise. The two types of tuples will behave the same most of "
+                "the time, but will print differently and be treated differently by "
+                "the compiler.")
+    },
     {NULL, NULL, NULL}
 };
 

test/suite3.janet

@@ -351,4 +351,12 @@
 (def t (put @{} :hi 1))
 (assert (deep= t @{:hi 1}) "regression #24")
 
+# Tuple types
+
+(assert (= (tuple/type '(1 2 3)) :parens) "normal tuple")
+(assert (= (tuple/type [1 2 3]) :parens) "normal tuple 1")
+(assert (= (tuple/type '[1 2 3]) :brackets) "bracketed tuple 2")
+(assert (= (tuple/type (-> '(1 2 3) marshal unmarshal)) :parens) "normal tuple marshalled/unmarshalled")
+(assert (= (tuple/type (-> '[1 2 3] marshal unmarshal)) :brackets) "normal tuple marshalled/unmarshalled")
+
 (end-suite)