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diff --git a/contrib/py-bindings/example.rst b/contrib/py-bindings/example.rst deleted file mode 100644 index 770c6e862..000000000 --- a/contrib/py-bindings/example.rst +++ /dev/null @@ -1,147 +0,0 @@ -Using the GF python bindings -============================ - -This is how to use some of the functionalities of the GF shell inside Python. - -Loading a pgf file ------------------- -First you must import the library: - ->>> import gf - -then load a PGF file, like this tiny example: - ->>> pgf = gf.read_pgf("Query.pgf") - -We could ask for the supported languages: - ->>> pgf.languages() -[QueryEng, QuerySpa] - -The *start category* of the PGF module is: - ->>> pgf.startcat() -Question - -Parsing and linearizing ------------------------ - -Let's us save the languages for later: - ->>> eng,spa = pgf.languages() - -These are opaque objects, not strings: - ->>> type(eng) -<type 'gf.lang'> - -and must be used when parsing: - ->>> pgf.parse(eng, "is 42 prime") -[Prime (Number 42)] - -Yes, I know it should have a '?' at the end, but there is not support for other lexers at this time. - -Notice that parsing returns a list of gf trees. -Let's save it and linearize it in Spanish: - ->>> t = pgf.parse(eng, "is 42 prime") ->>> pgf.linearize(spa, t[0]) -'42 es primo' - -(which is not, but there is a '?' lacking at the end, remember?) - - -Getting parsing completions ---------------------------- -One of the good things of the GF shell is that it suggests you which tokens can continue the line you are composing. - -We got this also in the bindings. -Suppose we have no idea on how to start: - ->>> pgf.complete(eng, "") -['is'] - -so, there is only a sensible thing to put in. Let's continue: - ->>> pgf.complete(eng, "is ") -[] - -Is it important to note the blank space at the end, otherwise we get it again: - ->>> pgf.complete(eng, "is") -['is'] - -But, how come that nothing is suggested at "is "? -At the current point, a literal integer is expected so GF would have to present an infinite list of alternatives. I cannot blame it for refusing to do so. - ->>> pgf.complete(eng, "is 42 ") -['even', 'odd', 'prime'] - -Good. I will go for 'even', just to be in the safe side: - ->>> pgf.complete(eng, "is 42 even ") -[] - -Nothin again, but this time the phrase is complete. Let us check it by parsing: - ->>> pgf.parse(eng, "is 42 even") -[Even (Number 42)] - -Deconstructing gf trees ------------------------ -We store the last result and ask for its type: - ->>> t = pgf.parse(eng, "is 42 even")[0] ->>> type(t) -<type 'gf.tree'> - -What's inside this tree? We use ``unapply`` for that: - ->>> t.unapply() -[Even, Number 42] - -This method returns a list with the head of the **fun** judgement and its arguments: - ->>> map(type, _) -[<type 'gf.cid'>, <type 'gf.expr'>] - - -Notice the argument is again a tree (``gf.tree`` or ``gf.expr``, it is all the same here.) - ->>> t.unapply()[1] -Number 42 - - -We will repeat the trick with it now: - ->>> t.unapply()[1].unapply() -[Number, 42] - -and again, the same structure shows up: - ->>> map(type, _) -[<type 'gf.cid'>, <type 'gf.expr'>] - -One more time, just to get to the bottom of it: - ->>> t.unapply()[1].unapply()[1].unapply() -42 - -but now it is an actual number: - ->>> type(_) -<type 'int'> - -We ended with a full decomposed **fun** judgement. - - -Note ----- - -This file can be used to test the bindings: :: - - python -m doctest example.rst - - - |