def apply(self, element):
# p < n
form = element.parent
ops = [element]
p = element.prev
n = element.next
args = [p, n]
form.remove(p) # < n
form.remove(n) # <
new_form = Form(Identifier(self.head_symbol_name))
new_form_element = form.replace(element, new_form) # (head_symbol)
while True: # while we find + e
e1 = new_form_element.next
if e1 is None: break
e2 = e1.next
if e2 is None: break
if is_identifier(e1.code) and e1.code.name in self.sym_vals: # if e1 is the same symbol as e, then it is the same operator
form.remove(e1)
form.remove(e2)
ops.append(e1)
args.append(e2)
else: break
for op in ops:
new_form.append(op)
new_form.append(Seq(*args))
return new_form_element.next
def apply(self, element):
# p + n
# + p n
# (+ p n)
form = element.parent
head = element.code
p = element.prev
n = element.next
form.remove(p) # + n
form.remove(n) # +
new_form = Form(head, p, n) # + (+ p n)
new_form_element = form.replace(element, new_form) # (+ p n)
while True: # while we find + e
e1 = new_form_element.next
if e1 is None: break
e2 = e1.next
if e2 is None: break
if is_identifier(e1.code, head.name): # if e1 is the same symbol as e, then it is the same operator
form.remove(e1)
form.remove(e2)
new_form.append(e2) # so we add the next element as an operand
else: break
return new_form_element.next
def apply(self, element):
# p < n
form = element.parent
ops = [element]
p = element.prev
n = element.next
args = [p, n]
form.remove(p) # < n
form.remove(n) # <
new_form = Form(Identifier(self.head_symbol_name))
new_form_element = form.replace(element, new_form) # (head_symbol)
while True: # while we find + e
e1 = new_form_element.next
if e1 is None: break
e2 = e1.next
if e2 is None: break
if is_identifier(
e1.code
) and e1.code.name in self.sym_vals: # if e1 is the same symbol as e, then it is the same operator
form.remove(e1)
form.remove(e2)
ops.append(e1)
args.append(e2)
else:
break
for op in ops:
new_form.append(op)
new_form.append(Seq(*args))
return new_form_element.next
