14ccdeb4d7
Pattern objects have two additional parameters for the ::search and ::match methods to define the starting and ending position of the subject within the string to be searched. This allows for searching a sub-string without creating a slice. However, one caveat of using the start-pos rather than a slice is that the start anchor (`^`) remains anchored to the beginning of the text. Signed-off-by: Jared Hancock <jared@greezybacon.me>
78 lines
1.3 KiB
Python
78 lines
1.3 KiB
Python
# test start and end pos specification
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try:
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import re
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except ImportError:
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print("SKIP")
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raise SystemExit
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def print_groups(match):
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print("----")
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try:
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if match is not None:
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i = 0
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while True:
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print(match.group(i))
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i += 1
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except IndexError:
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pass
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p = re.compile(r"o")
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m = p.match("dog")
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print_groups(m)
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m = p.match("dog", 1)
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print_groups(m)
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m = p.match("dog", 2)
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print_groups(m)
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# No match past end of input
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m = p.match("dog", 5)
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print_groups(m)
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m = p.match("dog", 0, 1)
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print_groups(m)
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# Caret only matches the actual beginning
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p = re.compile(r"^o")
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m = p.match("dog", 1)
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print_groups(m)
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# End at beginning means searching empty string
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p = re.compile(r"o")
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m = p.match("dog", 1, 1)
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print_groups(m)
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# End before the beginning doesn't match anything
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m = p.match("dog", 2, 1)
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print_groups(m)
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# Negative starting values don't crash
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m = p.search("dog", -2)
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print_groups(m)
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m = p.search("dog", -2, -5)
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print_groups(m)
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# Search also works
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print("--search")
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p = re.compile(r"o")
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m = p.search("dog")
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print_groups(m)
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m = p.search("dog", 1)
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print_groups(m)
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m = p.search("dog", 2)
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print_groups(m)
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# Negative starting values don't crash
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m = p.search("dog", -2)
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print_groups(m)
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m = p.search("dog", -2, -5)
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print_groups(m)
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