Package lepl :: Package regexp :: Module str :: Class StrParser

Class StrParser

Construct a parser for string based expressions.

We need a clear policy on backslashes. To be as backwards compatible as possible I am going with:

"Escaping" means prefixing with .

These characters are special: {, }, [, ], -, , (, ), *, ?, ., +, ^, $, |.

Special characters (ie literal, or unescaped special characters) may not have a meaning currently, or may only have a meaning in certain contexts.

To use a special character literally, it must be escaped.

If a special character is used without an escape, in a context where it doesn't have a meaning, then it is an error.

If a non-special character is escaped, that is also an error.

This is not the same as the Python convention, but I believe it makes automatic escaping of given text easier.

Instance Methods

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__init__(self, alphabet)
x.__init__(...) initializes x; see help(type(x)) for signature

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dup(self, x)
Create an interval from a single character.

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tup(self, x)
Create an interval from a tuple.

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dot(self, _)
Create a "complete" interval.

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invert(self, x)
Invert an interval.

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sequence(self, x)
Create a sequence.

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star(self, x)
Repeat a sub-expression.

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plus(self, x)
Repeat a sub-expression.

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option(self, x)
Make a sub-expression optional.

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choice(self, x)
Construct a choice from a list of sub-expressions.

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char(self, x)
Construct a character from an interval (pair).

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extend(self, x)
Delegate a character extension to the alphabet.

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build(self)
Construct the parser.

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Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __new__, __reduce__, __reduce_ex__, __repr__, __setattr__, __sizeof__, __str__, __subclasshook__

Properties

[hide private]

Inherited from object: __class__

Method Details

[hide private]

init(self, alphabet)
(Constructor)

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x.__init__(...) initializes x; see help(type(x)) for signature

Overrides: object.__init__: (inherited documentation)

Class StrParser

__init__(self, alphabet) (Constructor)

init(self, alphabet)
(Constructor)