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#
# ebnftest_number_parser.py
#
# BNF from number_parser.py:
#
# optional_and ::= ["and" | "-"]
# optional_dash ::= ["-"]
# units ::= "one" | "two" | "three" | ... | "nine"
# tens ::= "twenty" | "thirty" | ... | "ninety"
# one_to_99 ::= units | ten | teens | (tens [optional_dash units])
# ten ::= "ten"
# teens ::= "eleven" | "twelve" | ... | "nineteen"
# hundreds ::= (units | teens_only | tens optional_dash units) "hundred"
# thousands ::= one_to_99 "thousand"
#
# # number from 1-999,999
# number ::= [thousands [optional_and]] [hundreds[optional_and]] one_to_99
# | [thousands [optional_and]] hundreds
# | thousands
#
import ebnf
grammar = """
(*
EBNF for number_words.py
*)
number = [thousands, [and]], [hundreds, [and]], [one_to_99];
thousands = one_to_99, "thousand";
hundreds_mult = units | teens | multiples_of_ten, ["-"], units;
hundreds = hundreds_mult, "hundred";
teens =
"eleven"
| "twelve"
| "thirteen"
| "fourteen"
| "fifteen"
| "sixteen"
| "seventeen"
| "eighteen"
| "nineteen"
;
one_to_99 = units | teens | ten | multiples_of_ten, [["-"], units];
ten = "ten";
multiples_of_ten = "twenty" | "thirty" | "forty" | "fifty" | "sixty" | "seventy" | "eighty" | "ninety";
units = "one" | "two" | "three" | "four" | "five" | "six" | "seven" | "eight" | "nine";
and = "and" | "-";
"""
parsers = ebnf.parse(grammar)
number_parser = parsers["number"]
try:
number_parser.create_diagram("ebnf_number_parser_diagram.html")
except Exception as e:
print("Failed to create diagram for EBNF-generated number parser"
f" - {type(e).__name__}: {e}")
number_parser.run_tests(
"""
one
seven
twelve
twenty six
forty-two
two hundred
twelve hundred
one hundred and eleven
seven thousand and six
twenty five hundred and one
ninety nine thousand nine hundred and ninety nine
# invalid
twenty hundred
""",
full_dump=False
)
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