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"""
Handling Ambiguity
==================
A demonstration of ambiguity
This example shows how to use get explicit ambiguity from Lark's Earley parser.
"""
import sys
from lark import Lark, tree
grammar = """
sentence: noun verb noun -> simple
| noun verb "like" noun -> comparative
noun: adj? NOUN
verb: VERB
adj: ADJ
NOUN: "flies" | "bananas" | "fruit"
VERB: "like" | "flies"
ADJ: "fruit"
%import common.WS
%ignore WS
"""
parser = Lark(grammar, start='sentence', ambiguity='explicit')
sentence = 'fruit flies like bananas'
def make_png(filename):
tree.pydot__tree_to_png( parser.parse(sentence), filename)
def make_dot(filename):
tree.pydot__tree_to_dot( parser.parse(sentence), filename)
if __name__ == '__main__':
print(parser.parse(sentence).pretty())
# make_png(sys.argv[1])
# make_dot(sys.argv[1])
# Output:
#
# _ambig
# comparative
# noun fruit
# verb flies
# noun bananas
# simple
# noun
# fruit
# flies
# verb like
# noun bananas
#
# (or view a nicer version at "./fruitflies.png")
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