🐐 Array concat

centvrion/ast_nodes.py

@@ -59,7 +59,7 @@ def rep_join(l):
 OP_STR = {
   "SYMBOL_PLUS": "+", "SYMBOL_MINUS": "-",
   "SYMBOL_TIMES": "*", "SYMBOL_DIVIDE": "/",
-  "SYMBOL_AMPERSAND": "&",
+  "SYMBOL_AMPERSAND": "&", "SYMBOL_AT": "@",
   "KEYWORD_RELIQVVM": "RELIQVVM",
   "KEYWORD_EST": "EST", "KEYWORD_DISPAR": "DISPAR",
   "KEYWORD_MINVS": "MINVS",
@@ -833,6 +833,10 @@ class BinOp(Node):
           return vtable, ValNul()
         result = (lv or 0) + (rv or 0)
         return vtable, ValFrac(result) if isinstance(result, Fraction) else ValInt(result)
+      case "SYMBOL_AT":
+        if not isinstance(left, ValList) or not isinstance(right, ValList):
+          raise CentvrionError("@ requires two arrays")
+        return vtable, ValList(list(lv) + list(rv))
       case "SYMBOL_AMPERSAND":
         magnvm = "MAGNVM" in vtable["#modules"]
         svbnvlla = "SVBNVLLA" in vtable["#modules"]

centvrion/compiler/emit_expr.py

@@ -13,6 +13,7 @@ _BINOP_FN = {
   "SYMBOL_TIMES":     "cent_mul",
   "SYMBOL_DIVIDE":    "cent_div",
   "SYMBOL_AMPERSAND": "cent_concat",
+  "SYMBOL_AT":        "cent_array_concat",
   "KEYWORD_RELIQVVM": "cent_mod",
   "KEYWORD_EST":      "cent_eq",
   "KEYWORD_DISPAR":   "cent_neq",

centvrion/compiler/runtime/cent_runtime.c

@@ -409,6 +409,18 @@ CentValue cent_add(CentValue a, CentValue b) {
   return cent_null();
 }
 
+CentValue cent_array_concat(CentValue a, CentValue b) {
+  if (a.type != CENT_LIST || b.type != CENT_LIST)
+    cent_type_error("'@' requires two arrays");
+  int total = a.lval.len + b.lval.len;
+  CentValue result = cent_list_new(total);
+  for (int i = 0; i < a.lval.len; i++)
+    cent_list_push(&result, a.lval.items[i]);
+  for (int i = 0; i < b.lval.len; i++)
+    cent_list_push(&result, b.lval.items[i]);
+  return result;
+}
+
 CentValue cent_concat(CentValue a, CentValue b) {
   const char *sa = (a.type == CENT_NULL) ? "" : cent_make_string(a);
   const char *sb = (b.type == CENT_NULL) ? "" : cent_make_string(b);

centvrion/compiler/runtime/cent_runtime.h

@@ -198,6 +198,7 @@ char *cent_make_string(CentValue v);
 /* ------------------------------------------------------------------ */
 
 CentValue cent_add(CentValue a, CentValue b);  /* INT+INT or FRAC+FRAC/INT */
+CentValue cent_array_concat(CentValue a, CentValue b); /* @ operator: concatenate two arrays */
 CentValue cent_concat(CentValue a, CentValue b); /* & operator: coerce all types to str */
 CentValue cent_sub(CentValue a, CentValue b);  /* INT-INT or FRAC-FRAC/INT */
 CentValue cent_mul(CentValue a, CentValue b);  /* INT*INT or FRAC*FRAC/INT */

centvrion/lexer.py

@@ -94,6 +94,7 @@ symbol_tokens = [
   ("SYMBOL_TIMES", r"\*"),
   ("SYMBOL_DIVIDE", r"\/"),
   ("SYMBOL_AMPERSAND", r"&"),
+  ("SYMBOL_AT", r"@"),
   ("SYMBOL_COMMA", r",")
 ]
 

centvrion/parser.py

@@ -116,7 +116,7 @@ class Parser():
         ('left', ["KEYWORD_AVT"]),
         ('left', ["KEYWORD_ET"]),
         ('left', ["KEYWORD_PLVS", "KEYWORD_MINVS", "KEYWORD_EST", "KEYWORD_DISPAR"]),
-        ('left', ["SYMBOL_AMPERSAND", "SYMBOL_PLUS", "SYMBOL_MINUS"]),
+        ('left', ["SYMBOL_AMPERSAND", "SYMBOL_AT", "SYMBOL_PLUS", "SYMBOL_MINUS"]),
         ('left', ["SYMBOL_TIMES", "SYMBOL_DIVIDE", "KEYWORD_RELIQVVM"]),
         ('right', ["UMINUS", "UNOT"]),
         ('left', ["SYMBOL_LBRACKET", "INDEX"]),
@@ -311,6 +311,7 @@ class Parser():
     def expression_nullus(_):
       return ast_nodes.Nullus()
 
+    @self.pg.production('expression : expression SYMBOL_AT expression')
     @self.pg.production('expression : expression SYMBOL_AMPERSAND expression')
     @self.pg.production('expression : expression SYMBOL_MINUS expression')
     @self.pg.production('expression : expression SYMBOL_PLUS expression')