HaskellWorks.Data.BalancedParens.Internal.Slow.FindUnmatchedCloseFar.Vector8

Documentation

findUnmatchedCloseFar :: Word64 -> Word64 -> Vector Word8 -> Word64

Find the position of the first unmatch parenthesis.

The digits 1 and 0 are treated as an open parenthesis and closing parenthesis respectively.

All positions are indexed from zero. If the search runs out of bits, then continue as if there remain an infinite string of zeros.

>>> import HaskellWorks.Data.Bits.BitRead
>>> import Data.Maybe

The following scans for the first unmatched closing parenthesis from the beginning of the bit string:

>>> findUnmatchedCloseFar 0 0 $ fromJust $ bitRead "00000000"
0

The following scans for the first unmatched closing parenthesis after skipping one bit from the beginning of the bit string:

>>> findUnmatchedCloseFar 0 1 $ fromJust $ bitRead "00000000"
1

The following scans for the first unmatched closing parenthesis from the beginning of the bit string. To find unmatched parenthesis, the scan passes over the first parent of matching parentheses:

>>> findUnmatchedCloseFar 0 0 $ fromJust $ bitRead "10000000"
2

The following scans for the first unmatched closing parenthesis from the beginning of the bit string, but runs out of bits. The scan continues as if there an inifinite string of zero bits follows, the first of which is at position 64, which also happens to be the position of the unmatched parenthesis.

>>> findUnmatchedCloseFar 0 0 $ fromJust $ bitRead "11110000"
8

The following scans for the first unmatched closing parenthesis from the beginning of the bit string, but runs out of bits. The scan continues as if there an inifinite string of zero bits follows and we don't get to the unmatched parenthesis until position 128.

>>> findUnmatchedCloseFar 0 0 $ fromJust $ bitRead "11111111"
16

Following are some more examples:

>>> findUnmatchedCloseFar 0 0 $ fromJust $ bitRead "11110000"
8
>>> findUnmatchedCloseFar 0 1 $ fromJust $ bitRead "11110000"
7
>>> findUnmatchedCloseFar 0 2 $ fromJust $ bitRead "11110000"
6
>>> findUnmatchedCloseFar 0 3 $ fromJust $ bitRead "11110000"
5
>>> findUnmatchedCloseFar 0 4 $ fromJust $ bitRead "11110000"
4
>>> findUnmatchedCloseFar 0 5 $ fromJust $ bitRead "11110000"
5
>>> findUnmatchedCloseFar 0 6 $ fromJust $ bitRead "11110000"
6
>>> findUnmatchedCloseFar 0 7 $ fromJust $ bitRead "11110000"
7
>>> findUnmatchedCloseFar 0 8 $ fromJust $ bitRead "11110000"
8