+
+
+class SprintfStdout(object):
+ """
+ A context manager that captures outputs to stdout.
+
+ with SprintfStdout() as buf:
+ print("test")
+ print(buf())
+
+ 'test\n'
+ """
+ def __init__(self) -> None:
+ self.destination = io.StringIO()
+ self.recorder = None
+
+ def __enter__(self) -> Callable[[], str]:
+ self.recorder = contextlib.redirect_stdout(self.destination)
+ self.recorder.__enter__()
+ return lambda: self.destination.getvalue()
+
+ def __exit__(self, *args) -> None:
+ self.recorder.__exit__(*args)
+ self.destination.seek(0)
+ return None # don't suppress exceptions
+
+
+def is_are(n: int) -> str:
+ """Is or are?
+
+ >>> is_are(1)
+ 'is'
+ >>> is_are(2)
+ 'are'
+
+ """
+ if n == 1:
+ return "is"
+ return "are"
+
+
+def pluralize(n: int) -> str:
+ """Add an s?
+
+ >>> pluralize(15)
+ 's'
+ >>> count = 1
+ >>> print(f'There {is_are(count)} {count} file{pluralize(count)}.')
+ There is 1 file.
+ >>> count = 4
+ >>> print(f'There {is_are(count)} {count} file{pluralize(count)}.')
+ There are 4 files.
+
+ """
+ if n == 1:
+ return ""
+ return "s"
+
+
+def thify(n: int) -> str:
+ """Return the proper cardinal suffix for a number.
+
+ >>> thify(1)
+ 'st'
+ >>> thify(33)
+ 'rd'
+ >>> thify(16)
+ 'th'
+
+ """
+ digit = str(n)
+ assert is_integer_number(digit)
+ digit = digit[-1:]
+ if digit == "1":
+ return "st"
+ elif digit == "2":
+ return "nd"
+ elif digit == "3":
+ return "rd"
+ else:
+ return "th"
+
+
+def ngrams(txt: str, n: int):
+ """Return the ngrams from a string.
+
+ >>> [x for x in ngrams('This is a test', 2)]
+ ['This is', 'is a', 'a test']
+
+ """
+ words = txt.split()
+ for ngram in ngrams_presplit(words, n):
+ ret = ''
+ for word in ngram:
+ ret += f'{word} '
+ yield ret.strip()
+
+
+def ngrams_presplit(words: Sequence[str], n: int):
+ return list_utils.ngrams(words, n)
+
+
+def bigrams(txt: str):
+ return ngrams(txt, 2)
+
+
+def trigrams(txt: str):
+ return ngrams(txt, 3)
+
+
+def shuffle_columns_into_list(
+ input_lines: Iterable[str],
+ column_specs: Iterable[Iterable[int]],
+ delim=''
+) -> Iterable[str]:
+ """Helper to shuffle / parse columnar data and return the results as a
+ list. The column_specs argument is an iterable collection of
+ numeric sequences that indicate one or more column numbers to
+ copy.
+
+ >>> cols = '-rwxr-xr-x 1 scott wheel 3.1K Jul 9 11:34 acl_test.py'.split()
+ >>> shuffle_columns_into_list(
+ ... cols,
+ ... [ [8], [2, 3], [5, 6, 7] ],
+ ... delim=' ',
+ ... )
+ ['acl_test.py', 'scott wheel', 'Jul 9 11:34']
+
+ """
+ out = []
+
+ # Column specs map input lines' columns into outputs.
+ # [col1, col2...]
+ for spec in column_specs:
+ chunk = ''
+ for n in spec:
+ chunk = chunk + delim + input_lines[n]
+ chunk = chunk.strip(delim)
+ out.append(chunk)
+ return out
+
+
+def shuffle_columns_into_dict(
+ input_lines: Iterable[str],
+ column_specs: Iterable[Tuple[str, Iterable[int]]],
+ delim=''
+) -> Dict[str, str]:
+ """Helper to shuffle / parse columnar data and return the results
+ as a dict.
+
+ >>> cols = '-rwxr-xr-x 1 scott wheel 3.1K Jul 9 11:34 acl_test.py'.split()
+ >>> shuffle_columns_into_dict(
+ ... cols,
+ ... [ ('filename', [8]), ('owner', [2, 3]), ('mtime', [5, 6, 7]) ],
+ ... delim=' ',
+ ... )
+ {'filename': 'acl_test.py', 'owner': 'scott wheel', 'mtime': 'Jul 9 11:34'}
+
+ """
+ out = {}
+
+ # Column specs map input lines' columns into outputs.
+ # "key", [col1, col2...]
+ for spec in column_specs:
+ chunk = ''
+ for n in spec[1]:
+ chunk = chunk + delim + input_lines[n]
+ chunk = chunk.strip(delim)
+ out[spec[0]] = chunk
+ return out
+
+
+def interpolate_using_dict(txt: str, values: Dict[str, str]) -> str:
+ """Interpolate a string with data from a dict.
+
+ >>> interpolate_using_dict('This is a {adjective} {noun}.',
+ ... {'adjective': 'good', 'noun': 'example'})
+ 'This is a good example.'
+
+ """
+ return sprintf(txt.format(**values), end='')
+
+
+if __name__ == '__main__':
+ import doctest
+ doctest.testmod()