Comma-list declarations issue 2856

doc/source/language/variables.rst

@@ -92,6 +92,18 @@ Any variable declared with ``DECLARE``, ``DECLARE LOCAL``, or ``LOCAL``
 will only exist inside the code block section it was created in.
 After that code block is finished, the variable will no longer exist.
 
+It is also possible to declare multiple variables in a single ``DECLARE`` statement,
+separated by commas, as shown below::
+
+    // These all do the exact same thing - make local variables:
+    DECLARE A IS 5, B TO 1, C TO "O".
+    LOCAL A IS 5, B TO 1, C TO "O".
+    DECLARE LOCAL A IS 5, B TO 1, C TO "O".
+
+    // These do the exact same thing - make global variables:
+    GLOBAL A IS 5, B TO 1, C TO "O".
+    DECLARE GLOBAL A IS 5, B TO 1, C TO "O".
+
 See Scoping:
 ::::::::::::
 
@@ -268,6 +280,11 @@ This follows the :ref:`scoping rules explained below <scope>`.  If the
 variable can be found in the current local scope, or any scope higher
 up, then it won't be created and instead the existing one will be used.
 
+It is also possible to set the values of multiple variables in a single ``SET`` statement
+by separating the assignments with commas, as shown below::
+
+    SET X TO 1, Y TO 5, S TO "abc".
+
 .. _unset:
 
 ``UNSET``

kerboscript_tests/declaration/multi_declaration_test.ks

@@ -0,0 +1,30 @@
+// Tests comma-separated declarations of variables
+
+print "Testing with 'SET'".
+set a to 1, b to 2, c to "a".
+
+print " 1. The first variable has the correct value: " + (a = 1).
+print " 2. The second variable has the correct value: " + (b = 2).
+print " 3. The third variable has the correct value: " + (c = "a").
+
+print "Testing with 'GLOBAL'".
+global d is 5, e to 2.
+
+print " 1. The first variable has the correct value: " + (d = 5).
+print " 2. The second variable has the correct value: " + (e = 2).
+
+print "Testing with 'DECLARE'".
+
+declare f is 12, g to 1.
+
+print " 1. The first variable has the correct value: " + (f = 12).
+print " 2. The second variable has the correct value: " + (g = 1).
+
+
+print "Testing with 'DECLARE GLOBAL'".
+
+declare h is 7, i to 15, j to 3.
+
+print " 1. The first variable has the correct value: " + (h = 7).
+print " 2. The second variable has the correct value: " + (i = 15).
+print " 3. The thrid variable has the correct value: " + (j = 3).

src/kOS.Safe/Compilation/KS/Compiler.cs

@@ -2175,7 +2175,11 @@ private ParseNode DepthFirstLeftSearch(ParseNode node, TokenType tokType)
         private void VisitSetStatement(ParseNode node)
         {
             NodeStartHousekeeping(node);
-            ProcessSetOperation(node.Nodes[1], node.Nodes[3]);
+
+            for (int i = 1; i < node.Nodes.Count; i += 4)
+            {
+                ProcessSetOperation(node.Nodes[i], node.Nodes[i + 2]);
+            }
         }
 
         /// <summary>
@@ -2687,8 +2691,10 @@ private void VisitDeclareStatement(ParseNode node)
             //    DECLARE [GLOBAL|LOCAL] identifier TO expr.
             if (lastSubNode.Token.Type == TokenType.declare_identifier_clause)
             {
-                VisitNode(lastSubNode.Nodes[2]);
-                AddOpcode(CreateAppropriateStoreCode(whereToStore, true, "$" + GetIdentifierText(lastSubNode.Nodes[0])));
+                for (int i = 0; i < lastSubNode.Nodes.Count; i += 4) {
+                    VisitNode(lastSubNode.Nodes[i + 2]);
+                    AddOpcode(CreateAppropriateStoreCode(whereToStore, true, "$" + GetIdentifierText(lastSubNode.Nodes[i])));
+                }
             }
 
             // If the declare statement is of the form:

src/kOS.Safe/Compilation/KS/Parser.cs

@@ -453,6 +453,39 @@ private void Parseset_stmt(ParseNode parent) // NonTerminalSymbol: set_stmt
              // Concat Rule
             Parseexpr(node); // NonTerminal Rule: expr
 
+             // Concat Rule
+            tok = scanner.LookAhead(TokenType.COMMA); // ZeroOrMore Rule
+            while (tok.Type == TokenType.COMMA)
+            {
+
+                 // Concat Rule
+                tok = scanner.Scan(TokenType.COMMA); // Terminal Rule: COMMA
+                n = node.CreateNode(tok, tok.ToString() );
+                node.Token.UpdateRange(tok);
+                node.Nodes.Add(n);
+                if (tok.Type != TokenType.COMMA) {
+                    tree.Errors.Add(new ParseError("Unexpected token '" + tok.Text.Replace("\n", "") + "' found. Expected " + TokenType.COMMA.ToString(), 0x1001, tok));
+                    return;
+                }
+
+                 // Concat Rule
+                Parsevaridentifier(node); // NonTerminal Rule: varidentifier
+
+                 // Concat Rule
+                tok = scanner.Scan(TokenType.TO); // Terminal Rule: TO
+                n = node.CreateNode(tok, tok.ToString() );
+                node.Token.UpdateRange(tok);
+                node.Nodes.Add(n);
+                if (tok.Type != TokenType.TO) {
+                    tree.Errors.Add(new ParseError("Unexpected token '" + tok.Text.Replace("\n", "") + "' found. Expected " + TokenType.TO.ToString(), 0x1001, tok));
+                    return;
+                }
+
+                 // Concat Rule
+                Parseexpr(node); // NonTerminal Rule: expr
+            tok = scanner.LookAhead(TokenType.COMMA); // ZeroOrMore Rule
+            }
+
              // Concat Rule
             tok = scanner.Scan(TokenType.EOI); // Terminal Rule: EOI
             n = node.CreateNode(tok, tok.ToString() );
@@ -1332,6 +1365,65 @@ private void Parsedeclare_identifier_clause(ParseNode parent) // NonTerminalSymb
              // Concat Rule
             Parseexpr(node); // NonTerminal Rule: expr
 
+             // Concat Rule
+            tok = scanner.LookAhead(TokenType.COMMA); // ZeroOrMore Rule
+            while (tok.Type == TokenType.COMMA)
+            {
+
+                 // Concat Rule
+                tok = scanner.Scan(TokenType.COMMA); // Terminal Rule: COMMA
+                n = node.CreateNode(tok, tok.ToString() );
+                node.Token.UpdateRange(tok);
+                node.Nodes.Add(n);
+                if (tok.Type != TokenType.COMMA) {
+                    tree.Errors.Add(new ParseError("Unexpected token '" + tok.Text.Replace("\n", "") + "' found. Expected " + TokenType.COMMA.ToString(), 0x1001, tok));
+                    return;
+                }
+
+                 // Concat Rule
+                tok = scanner.Scan(TokenType.IDENTIFIER); // Terminal Rule: IDENTIFIER
+                n = node.CreateNode(tok, tok.ToString() );
+                node.Token.UpdateRange(tok);
+                node.Nodes.Add(n);
+                if (tok.Type != TokenType.IDENTIFIER) {
+                    tree.Errors.Add(new ParseError("Unexpected token '" + tok.Text.Replace("\n", "") + "' found. Expected " + TokenType.IDENTIFIER.ToString(), 0x1001, tok));
+                    return;
+                }
+
+                 // Concat Rule
+                tok = scanner.LookAhead(TokenType.TO, TokenType.IS); // Choice Rule
+                switch (tok.Type)
+                { // Choice Rule
+                    case TokenType.TO:
+                        tok = scanner.Scan(TokenType.TO); // Terminal Rule: TO
+                        n = node.CreateNode(tok, tok.ToString() );
+                        node.Token.UpdateRange(tok);
+                        node.Nodes.Add(n);
+                        if (tok.Type != TokenType.TO) {
+                            tree.Errors.Add(new ParseError("Unexpected token '" + tok.Text.Replace("\n", "") + "' found. Expected " + TokenType.TO.ToString(), 0x1001, tok));
+                            return;
+                        }
+                        break;
+                    case TokenType.IS:
+                        tok = scanner.Scan(TokenType.IS); // Terminal Rule: IS
+                        n = node.CreateNode(tok, tok.ToString() );
+                        node.Token.UpdateRange(tok);
+                        node.Nodes.Add(n);
+                        if (tok.Type != TokenType.IS) {
+                            tree.Errors.Add(new ParseError("Unexpected token '" + tok.Text.Replace("\n", "") + "' found. Expected " + TokenType.IS.ToString(), 0x1001, tok));
+                            return;
+                        }
+                        break;
+                    default:
+                        tree.Errors.Add(new ParseError("Unexpected token '" + tok.Text.Replace("\n", "") + "' found. Expected TO or IS.", 0x0002, tok));
+                        break;
+                } // Choice Rule
+
+                 // Concat Rule
+                Parseexpr(node); // NonTerminal Rule: expr
+            tok = scanner.LookAhead(TokenType.COMMA); // ZeroOrMore Rule
+            }
+
              // Concat Rule
             tok = scanner.Scan(TokenType.EOI); // Terminal Rule: EOI
             n = node.CreateNode(tok, tok.ToString() );

src/kOS.Safe/Compilation/KS/kRISC.tpg

@@ -153,7 +153,7 @@ directive            -> lazyglobal_directive; // Add to this list later if we ma
 // ------------ statements --------------------
 
 empty_stmt     -> EOI;
-set_stmt       -> SET varidentifier TO expr EOI;
+set_stmt       -> SET varidentifier TO expr (COMMA varidentifier TO expr)* EOI;
 if_stmt        -> IF expr instruction EOI? (ELSE instruction EOI?)?;
 until_stmt     -> UNTIL expr instruction EOI?;
 fromloop_stmt  -> FROM instruction_block UNTIL expr STEP instruction_block DO instruction EOI?;
@@ -172,7 +172,7 @@ remove_stmt    -> REMOVE expr EOI;
 log_stmt       -> LOG expr TO expr EOI;
 break_stmt     -> BREAK EOI;
 preserve_stmt  -> PRESERVE EOI;
-declare_identifier_clause -> IDENTIFIER (TO|IS) expr EOI;
+declare_identifier_clause -> IDENTIFIER (TO|IS) expr (COMMA IDENTIFIER (TO|IS) expr)* EOI;
 declare_parameter_clause  -> PARAMETER IDENTIFIER ((TO|IS) expr)? (COMMA IDENTIFIER ((TO|IS) expr)?)* EOI;
 declare_function_clause   -> FUNCTION IDENTIFIER instruction_block EOI?;
 declare_lock_clause       -> LOCK IDENTIFIER TO expr EOI;