Changeset 222 for branches/interpreter2/UTokenizer.pas

Timestamp:

Nov 25, 2020, 12:18:45 AM (4 years ago)

Author:

chronos

Message:

• Added: Support for more expression operators.
• Added: Support for brackets in expressions.

File:

• branches/interpreter2/UTokenizer.pas (modified) (5 diffs)

branches/interpreter2/UTokenizer.pas

@@ -53 +53 @@
     function GetNext: TToken;
     function CheckNext(Text: string; Kind: TTokenKind): Boolean;
+    function CheckNextAndRead(Text: string; Kind: TTokenKind): Boolean;
     function CheckNextKind(Kind: TTokenKind): Boolean;
+    function CheckNextKindAndRead(Kind: TTokenKind): Boolean;
     procedure Expect(Text: string; Kind: TTokenKind);
     procedure Error(Text: string);
@@ -111 +113 @@
   Result := (C = ';') or (C = '.') or (C = '(') or (C = ')') or (C = '=') or
     (C = ':') or (C = '+') or (C = '-') or (C = ',') or (C = '/') or
-    (C = '<') or (C = '>');
+    (C = '<') or (C = '>') or (C = '*');
 end;
 
 function TTokenizer.IsSpecialSymbol2(Text: string): Boolean;
 begin
-  Result := (Text = ':=') or (Text = '//') or (Text = '<>');
+  Result := (Text = ':=') or (Text = '//') or (Text = '<>') or (Text = '<=') or
+    (Text = '>=');
 end;
 
@@ -141 +144 @@
 function TTokenizer.IsOperator(Text: string): Boolean;
 begin
-  Result := (Text = '+') or (Text = '-') or (Text = '=') or (Text = '<>');
+  Result := (Text = '+') or (Text = '-') or (Text = '=') or (Text = '<>') or
+    (Text = '*') or (Text = '/') or (Text = 'div') or (Text = '<=') or
+    (Text = '>=') or (Text = 'mod') or (Text = 'shl') or (Text = 'shr') or
+    (Text = 'and') or (Text = 'or') or (Text = 'xor') or (Text = 'not') or
+    (Text = '>') or (Text = '<');
 end;
 
@@ -270 +277 @@
 end;
 
+function TTokenizer.CheckNextAndRead(Text: string; Kind: TTokenKind): Boolean;
+var
+  LastPos: TTokenizerPos;
+  Token: TToken;
+begin
+  LastPos := Pos;
+  Token := GetNext;
+  Result := (Token.Text = Text) and (Token.Kind = Kind);
+  if not Result then Pos := LastPos;
+end;
+
 function TTokenizer.CheckNextKind(Kind: TTokenKind): Boolean;
 var
@@ -281 +299 @@
 end;
 
+function TTokenizer.CheckNextKindAndRead(Kind: TTokenKind): Boolean;
+var
+  LastPos: TTokenizerPos;
+  Token: TToken;
+begin
+  LastPos := Pos;
+  Token := GetNext;
+  Result := Token.Kind = Kind;
+  if not Result then Pos := LastPos;
+end;
+
 procedure TTokenizer.Expect(Text: string; Kind: TTokenKind);
 var