Can do logical and.

interpreter.py

@@ -841,6 +841,8 @@ class Interpreter():
             return self.evaluate_arraystatement(cur)
         elif isinstance(cur, nodes.IntStatement):
             return cur
+        elif isinstance(cur, nodes.AndStatement):
+            return self.evaluate_andstatement(cur)
         else:
             raise InvalidCode("Unknown statement.")
 
@@ -1229,7 +1231,22 @@ class Interpreter():
             return val1 != val2
         else:
             raise InvalidCode('You broke me.')
-    
+
+    def evaluate_andstatement(self, cur):
+        l = self.evaluate_statement(cur.left)
+        if isinstance(l, nodes.BoolStatement):
+            l = l.get_value()
+        if not isinstance(l, bool):
+            raise InterpreterException('First argument to "and" is not a boolean.')
+        if not l:
+            return False
+        r = self.evaluate_statement(cur.right)
+        if isinstance(r, nodes.BoolStatement):
+            r = r.get_value()
+        if not isinstance(r, bool):
+            raise InterpreterException('Second argument to "and" is not a boolean.')
+        return r
+
     def evaluate_arraystatement(self, cur):
         (arguments, kwargs) = self.reduce_arguments(cur.get_args())
         if len(kwargs) > 0:

mparser.py

@@ -27,6 +27,9 @@ reserved = {'true' : 'TRUE',
             'if' : 'IF',
             'endif' : 'ENDIF',
             'else' : 'ELSE',
+            'and' : 'AND',
+            'or' : 'OR',
+            'not' : 'NOT',
             }
 
 tokens = ['LPAREN',
@@ -62,6 +65,16 @@ t_COLON = ':'
 
 t_ignore = ' \t'
 
+precedence = (
+('left', 'COMMA'),
+('left', 'ASSIGN'),
+('nonassoc', 'EQUALS', 'NEQUALS'),
+('left', 'OR'),
+('left', 'AND'),
+('nonassoc', 'COLON')
+('left', 'DOT'),
+)
+
 def t_ATOM(t):
     '[a-zA-Z][_0-9a-zA-Z]*'
     t.type = reserved.get(t.value, 'ATOM')
@@ -175,6 +188,14 @@ def p_statement_if(t):
     'statement : IF statement EOL codeblock elseblock ENDIF'
     t[0] = nodes.IfStatement(t[2], t[4], t[5], t.lineno(1))
 
+def p_statement_parentheses(t):
+    'statement : LPAREN statement RPAREN'
+    t[0] = t[2]
+
+def p_statement_and(t):
+    'statement : statement AND statement'
+    t[0] = nodes.AndStatement(t[1], t[3])
+
 def p_empty_else(t):
     'elseblock : '
     return None

nodes.py

@@ -82,6 +82,18 @@ class IntStatement(Statement):
     def get_value(self):
         return self.value
 
+class AndStatement(Statement):
+    def __init__(self, left, right):
+        Statement.__init__(self, left.lineno)
+        self.left = left
+        self.right = right
+
+class OrStatement(Statement):
+    def __init__(self, left, right):
+        Statement.__init__(self, left.lineno)
+        self.left = left
+        self.right = right
+
 class IfStatement(Statement):
     def __init__(self, clause, trueblock, falseblock, lineno):
         Statement.__init__(self, lineno)

test cases/common/40 logic ops/meson.build

@@ -0,0 +1,46 @@
+project('logicopts', 'c')
+
+t = true
+f = false
+
+if (true)
+  message('Ok.')
+else
+  error('Not ok.')
+endif
+
+if (false)
+  error('Not ok.')
+else
+  message('Ok.')
+endif
+
+if (f)
+  error('Not ok.')
+else
+  message('Ok.')
+endif
+
+if (t)
+  message('Ok.')
+else
+  error('Not ok.')
+endif
+
+if t and t
+  message('Ok.')
+else
+  error('Not ok.')
+endif
+
+if t and f
+  error('Not ok.')
+else
+  message('Ok.')
+endif
+
+if f and t
+  error('Not ok.')
+else
+  message('Ok.')
+endif