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A scanner holds a buffer for lookahead parsing and has the
ability to scan for special symbols and indicators in that
buffer.
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Methods
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__getitem__
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__getitem__ ( self, index )
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__getslice__
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__getslice__ (
self,
start,
stop,
)
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__init__
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__init__ (
self,
prefix,
data='',
)
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__len__
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__len__ ( self )
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__nonzero__
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__nonzero__ ( self )
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acquire
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acquire ( self )
Lock the scanner so it doesn't destroy data on sync.
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advance
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advance ( self, count=1 )
Advance the pointer count characters.
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check
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check (
self,
i,
archetype=None,
)
Scan for the next single or triple quote, with the specified
archetype. Return the found quote or None.
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Exceptions
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TransientParseError, "need to scan for rest of quote"
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chop
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chop (
self,
count=None,
slop=0,
)
Chop the first count + slop characters off the front, and return
the first count. If count is not specified, then return
everything.
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Exceptions
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TransientParseError, "not enough data to read"
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complex
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complex (
self,
enter,
exit,
start=0,
end=None,
skip=None,
)
Scan from i for an ending sequence, respecting quotes,
entries and exits.
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Exceptions
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TransientParseError, "expecting end of complex expression"
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feed
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feed ( self, data )
Feed some more data to the scanner.
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find
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find (
self,
sub,
start=0,
end=None,
)
Find the next occurrence of the character, or return -1.
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last
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last (
self,
char,
start=0,
end=None,
)
Find the first character that is not the specified character.
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Exceptions
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TransientParseError, "expecting other than %s" % char
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nested
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nested (
self,
enter,
exit,
start=0,
end=None,
)
Scan from i for an ending sequence, respecting entries and exits
only.
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Exceptions
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TransientParseError, "expecting end of complex expression"
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next
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next (
self,
target,
start=0,
end=None,
mandatory=False,
)
Scan for the next occurrence of one of the characters in
the target string; optionally, make the scan mandatory.
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Exceptions
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ParseError, "expecting %s, not found" % target
TransientParseError, "expecting ending character"
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one
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one ( self )
Parse and return one token, or None if the scanner is empty.
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Exceptions
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ParseError, "unknown markup: %s%s" %( self.prefix, first )
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phrase
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phrase ( self, start=0 )
Scan from i for a phrase (e.g., word, f(a, b, c), 'a[i]', or
combinations like 'x[i](a)'.
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Exceptions
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ParseError, "curly braces can't open simple expressions"
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quote
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quote (
self,
start=0,
end=None,
mandatory=False,
)
Scan for the end of the next quote.
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Exceptions
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ParseError, "expecting end of string literal"
TransientParseError, "expecting end of string literal"
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read
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read (
self,
i=0,
count=1,
)
Read count chars starting from i; raise a transient error if
there aren't enough characters remaining.
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Exceptions
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TransientParseError, "need more data to read"
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release
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release ( self )
Unlock the scanner.
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rest
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rest ( self )
Get the remainder of the buffer.
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retreat
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retreat ( self, count=1 )
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Exceptions
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ParseError, "can't retreat back over synced out chars"
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set
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set ( self, data )
Start the scanner digesting a new batch of data; start the pointer
over from scratch.
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simple
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simple ( self, start=0 )
Scan from i for a simple expression, which consists of one
more phrases separated by dots.
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sync
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sync ( self )
Sync up the buffer with the read head.
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unsync
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unsync ( self )
Undo changes; reset the read head.
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word
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word ( self, start=0 )
Scan from i for a simple word.
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Exceptions
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TransientParseError, "expecting end of word"
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