Added list '[]' data type. Fix: function with no arguments

2024-03-28 08:51:02 +01:00
parent 3ca415fc66
commit c36c88d0fd
3 changed files with 99 additions and 27 deletions
@@ -21,6 +21,58 @@ func NewParser(ctx exprContext) (p *parser) {
 	return p
 }

+func (self *parser) parseFunction(scanner *scanner, tk *Token) (tree *term, err error) {
+	name, _ := tk.Value.(string)
+	funcObj := self.ctx.GetFuncInfo(name)
+	if funcObj == nil {
+		err = fmt.Errorf("unknown function %q", name)
+		return
+	}
+	maxArgs := funcObj.MaxArgs()
+	if maxArgs < 0 {
+		maxArgs = funcObj.MinArgs() + 10
+	}
+	args := make([]*term, 0, maxArgs)
+	lastSym := SymUnknown
+	for lastSym != SymClosedRound && lastSym != SymEos {
+		var subTree *ast
+		if subTree, err = self.parse(scanner, SymComma, SymClosedRound); err == nil {
+			if subTree.root != nil {
+				args = append(args, subTree.root)
+			}
+		} else {
+			break
+		}
+		lastSym = scanner.Previous().Sym
+	}
+	if err == nil {
+		// TODO Check arguments
+		tree = newFuncTerm(tk, args)
+	}
+	return
+}
+
+func (self *parser) parseList(scanner *scanner) (tree *term, err error) {
+	args := make([]*term, 0)
+	lastSym := SymUnknown
+	for lastSym != SymClosedSquare && lastSym != SymEos {
+		var subTree *ast
+		if subTree, err = self.parse(scanner, SymComma, SymClosedSquare); err == nil {
+			if subTree.root != nil {
+				args = append(args, subTree.root)
+			}
+		} else {
+			break
+		}
+		lastSym = scanner.Previous().Sym
+	}
+	if err == nil {
+		// TODO Check arguments
+		tree = newListTerm(args)
+	}
+	return
+}
+
 func (self *parser) parse(scanner *scanner, termSymbols ...Symbol) (tree *ast, err error) {
 	tree = NewAst()
 	firstToken := true
@@ -38,40 +90,24 @@ func (self *parser) parse(scanner *scanner, termSymbols ...Symbol) (tree *ast, e
 			}
 		}
 		firstToken = false
-		if tk.Sym == SymOpenRound {
+		switch tk.Sym {
+		case SymOpenRound:
 			var subTree *ast
 			if subTree, err = self.parse(scanner, SymClosedRound); err == nil {
 				subTree.root.priority = priValue
 				tree.addTerm(subTree.root)
 			}
-		} else if tk.Sym == SymFunction {
-			name, _ := tk.Value.(string)
-			funcObj := self.ctx.GetFuncInfo(name)
-			if funcObj == nil {
-				err = fmt.Errorf("unknown function %q", name)
-				break
+		case SymFunction:
+			var funcTerm *term
+			if funcTerm, err = self.parseFunction(scanner, tk); err == nil {
+				err = tree.addTerm(funcTerm)
 			}
-			maxArgs := funcObj.MaxArgs()
-			if maxArgs < 0 {
-				maxArgs = funcObj.MinArgs() + 10
+		case SymOpenSquare:
+			var listTerm *term
+			if listTerm, err = self.parseList(scanner); err == nil {
+				err = tree.addTerm(listTerm)
 			}
-			args := make([]*term, 0, maxArgs)
-			lastSym := SymUnknown
-			for lastSym != SymClosedRound && lastSym != SymEos {
-				var subTree *ast
-				if subTree, err = self.parse(scanner, SymComma, SymClosedRound); err == nil {
-					args = append(args, subTree.root)
-				} else {
-					break
-				}
-				lastSym = scanner.Previous().Sym
-			}
-			if err == nil {
-				// TODO Check arguments
-				t := newFuncTerm(tk, args)
-				tree.addTerm(t)
-			}
-		} else {
+		default:
 			err = tree.addToken(tk)
 		}
 	}