def find_first(prod) :
list_first_production = []
bool_epsilon = True
list_elem_prod = first.segment_production_into_terminals_and_non_terminals(prod)
for elem in list_elem_prod :
print elem + ' ---- '
list_first_production += []
list_first_production += first_table[elem]
if not '@' in list_first_production :
bool_epsilon = False
break
# end for
firsts = list(set(list_first_production))
#print firsts
if '@' in firsts :
return firsts.remove('@'), bool_epsilon
else :
return firsts, bool_epsilon
def generate_follow_variables() :
global graph
augmented_dic = {}
for elem in graph :
for prod in graph[elem] :
segmented_production = first.segment_production_into_terminals_and_non_terminals(prod)
len_of_production = len(segmented_production)
for i in range(len_of_production - 1) :
if segmented_production[i] in augmented_dic :
augmented_dic[segmented_production[i]] += [update_aug(segmented_production[i + 1:] + [elem])]
else :
augmented_dic[segmented_production[i]] = [update_aug(segmented_production[i + 1:] + [elem])]
#end loop
#linking last element to the BOSS
if segmented_production[len_of_production - 1] in augmented_dic :
augmented_dic[segmented_production[len_of_production - 1]] += [update_aug([elem])]
else :
augmented_dic[segmented_production[len_of_production - 1]] = [update_aug([elem])]
#end 2nd inner loop
#end outer loop
return augmented_dic
def generate_follow_variables():
global graph, set_terminal, set_non_terminal
augmented_dic = {}
for elem in graph:
for prod in graph[elem]:
segmented_production = first.segment_production_into_terminals_and_non_terminals(
prod)
len_of_production = len(segmented_production)
for i in range(len_of_production - 1):
if segmented_production[i] in augmented_dic:
augmented_dic[segmented_production[i]] += [
update_aug(segmented_production[i + 1:] + [elem])
]
else:
augmented_dic[segmented_production[i]] = [
update_aug(segmented_production[i + 1:] + [elem])
]
#end loop
#linking last element to the BOSS
if segmented_production[len_of_production - 1] in augmented_dic:
augmented_dic[segmented_production[len_of_production -
1]] += [update_aug([elem])]
else:
augmented_dic[segmented_production[len_of_production -
1]] = [update_aug([elem])]
#end 2nd inner loop
#end outer loop
for elem in set_non_terminal:
#print elem
if not elem in augmented_dic:
print "yes"
augmented_dic[elem] = [[]]
#covering the loop hole
#print augmented_dic
#print "--Augmented dic----"
return augmented_dic