Added functions to util.py.

1 files changed, 30 insertions, 18 deletions

diff --git a/python/util.py b/python/util.py
index 390b831..f149953 100644
--- a/python/util.py
+++ b/python/util.py
@@ -1,12 +1,16 @@
 #!/usr/bin/python
 
 import io
+import re
 from tokenize import tokenize
 
-# Check if code contains a sequence of tokens (given as a list of strings).
-def has_token_sequence(code, sequence):
+def get_tokens(code):
+    """ Gets a list of tokens. """
     stream = io.BytesIO(code.encode('utf-8'))
-    tokens = [t.string for t in tokenize(stream.readline) if t.string]
+    return [t.string for t in tokenize(stream.readline) if t.string]
+
+# Check if tokens contain a sequence of tokens (given as a list of strings).
+def has_token_sequence(tokens, sequence):
     for i in range(len(tokens)-len(sequence)+1):
         if tokens[i:i+len(sequence)] == sequence:
             return True
@@ -16,23 +20,31 @@ def almost_equal(a, b, prec=1):
     """ Compares values a and b using at most <code>prec</code> decimal values. """
     return int(a*10**prec) == int(b*10**prec)
 
+def get_numbers(s):
+    """ Extracts numbers from string s. """
+    str_vals = re.findall(r'''
+        [-+]? # optional sign
+        (?:
+             (?: \d* \. \d+ ) # .1 .12 .123 etc 9.1 etc 98.1 etc
+             |
+             (?: \d+ \.? ) # 1. 12. 123. etc 1 12 123 etc
+        )
+        # followed by optional exponent part if desired
+        (?: [Ee] [+-]? \d+ ) ?
+        ''', s, re.VERBOSE)
+    return [float(v) for v in str_vals]
+
 def string_almost_equal(s, a, prec=1):
-    """ Searches string s for a value that is almost equal to a.
-
-    Args:
-        s (str): string to search
-        a (float): value to find in string
-
-    Returns:
-        bool: True if successful, else False
-    """
-    for v in s.split():
-        try:
-            if almost_equal(float(v), a, prec):
+    """ Searches string s for a value that is almost equal to a. """
+    for v in get_numbers(s):
+        if almost_equal(v, a, prec):
                 return True
-        except:
-            pass
-    return False 
+    return False
+
+def string_contains_number(s, a):
+    """ Searches string s for a value that is equal to a. """
+    return a in get_numbers(s)
+
 
 if __name__ == '__main__':
     print(has_token_sequence('x + y >= 0', ['>=', '0']))