X-Git-Url: https://wannabe.guru.org/gitweb/?a=blobdiff_plain;ds=sidebyside;f=string_utils.py;h=45cf5aab7ac7f5202346745de733c792c984214d;hb=b843703134a166013518c707fa5a77373f1bf0bf;hp=7ad9c42a1e2af3304e18ba6beba021c35acbb086;hpb=3bc4daf1edc121cd633429187392227f2fa61885;p=python_utils.git

diff --git a/string_utils.py b/string_utils.py
index 7ad9c42..45cf5aa 100644
--- a/string_utils.py
+++ b/string_utils.py
@@ -1,19 +1,18 @@
 #!/usr/bin/env python3
 
+import contextlib
 import datetime
+import io
 from itertools import zip_longest
 import json
 import logging
 import random
 import re
 import string
-from typing import Any, List, Optional
+from typing import Any, Callable, Iterable, List, Optional
 import unicodedata
 from uuid import uuid4
 
-import dateparse.dateparse_utils as dp
-
-
 logger = logging.getLogger(__name__)
 
 NUMBER_RE = re.compile(r"^([+\-]?)((\d+)(\.\d+)?([e|E]\d+)?|\.\d+)$")
@@ -228,10 +227,14 @@ def strip_escape_sequences(in_str: str) -> str:
     return in_str
 
 
-def add_thousands_separator(in_str: str, *, separator_char = ',', places = 3) -> str:
+def add_thousands_separator(
+        in_str: str,
+        *,
+        separator_char = ',',
+        places = 3
+) -> str:
     if isinstance(in_str, int):
         in_str = f'{in_str}'
-
     if is_number(in_str):
         return _add_thousands_separator(
             in_str,
@@ -815,6 +818,7 @@ def to_bool(in_str: str) -> bool:
 
 
 def to_date(in_str: str) -> Optional[datetime.date]:
+    import dateparse.dateparse_utils as dp
     try:
         d = dp.DateParser()
         d.parse(in_str)
@@ -825,6 +829,7 @@ def to_date(in_str: str) -> Optional[datetime.date]:
 
 
 def valid_date(in_str: str) -> bool:
+    import dateparse.dateparse_utils as dp
     try:
         d = dp.DateParser()
         _ = d.parse(in_str)
@@ -835,6 +840,7 @@ def valid_date(in_str: str) -> bool:
 
 
 def to_datetime(in_str: str) -> Optional[datetime.datetime]:
+    import dateparse.dateparse_utils as dp
     try:
         d = dp.DateParser()
         dt = d.parse(in_str)
@@ -917,6 +923,22 @@ def sprintf(*args, **kwargs) -> str:
     return ret
 
 
+class SprintfStdout(object):
+    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:
     if n == 1:
         return "is"
@@ -941,3 +963,21 @@ def thify(n: int) -> str:
         return "rd"
     else:
         return "th"
+
+
+def ngrams(txt: str, n: int):
+    words = txt.split()
+    return ngrams_presplit(words, n)
+
+
+def ngrams_presplit(words: Iterable[str], n: int):
+    for ngram in zip(*[words[i:] for i in range(n)]):
+        yield(' '.join(ngram))
+
+
+def bigrams(txt: str):
+    return ngrams(txt, 2)
+
+
+def trigrams(txt: str):
+    return ngrams(txt, 3)