[bpt/coccinelle.git] / pycaml / pycaml.html

<html>
<head>
<title>Module Pycaml</title>
</head>
<body>
<table border=0 width="100%"><tr><td bgcolor="#c0c0c0">
<h1>Pycaml</h1>
</td></tr></table>
<p>
<h2>What is Pycaml</h2>
A library written by <a href=mailto:arty@users.sourceforge.net>
arty@users.sourceforge.net</a> which follows the Python/C API as
closely as possible, while
providing equivalent functionality for objective caml.  This is built
against python 2.x and Ocaml 3.04.<p>  It is intended to allow users to
build native ocaml libraries and use them from python, and alternately,
in order to allow ocaml users to benefit from linkable libraries provided
for python.<p>
I created this library in order to take advantage of python binding for
certain native libraries from ocaml.  While it is true that I could have
written new interfaces specifically for ocaml, the python interface is
sufficient for my needs, and this project was easier.<p>

<b>Note:</b> Unfortunately, the symbol <tt>init_exceptions</tt> exists in
both compiled ocaml code, and the python runtime.  In order to proceed, you
must rename this symbol either in the ocaml distribution (in byterun/fail.c,
and byterun/startup.c), or in the python distribution, and rebuild the 
software appropriately.<p>

Please edit the <tt>Makefile</tt> to put in your system's libraries used for
compiling programs embedded with python.  This library compiles on most
linux boxes without modification.  The python interpreter is used to determine
the path to the python library and must be in your path when you run make.
<p>

<b>Get the distribution here:</b><a href=pycaml.tar.gz>pycaml.tar.gz</a><p>

Because these are made to closely mirror the python API, the user should
become familiar with the python API.<p>
Given Ocaml parameter passing convention, it was convenient to pass multiple
arguments as members of a tuple, but single arguments without.  Consequently,
functions with arity 1, such as pytuple_new are called as<p>
<pre>
  pytuple_new 3 ;;
</pre><p>
And functions with more arguments are called as<p>
<pre>
  pydict_getitemstring (dict,"keystring") ;;
</pre>

<h2>Module Pycaml</h2>

<h3>Visible Types</h3>

<table border=0>
<tr bgcolor="#c0c0c0"><td>type</td><td width="100%">pyobject</td></tr>
<tr><td colspan=2>
The abstract type of python objects.
</td></tr>
<tr bgcolor="#c0c0c0"><td>type</td><td>pyobject_type =</td></tr>
<tr><td align=right></td><td>TupleType</td></tr>
<tr><td align=right>|</td><td>StringType</td></tr>
<tr><td align=right>|</td><td>IntType</td></tr>
<tr><td align=right>|</td><td>FloatType</td></tr>
<tr><td align=right>|</td><td>ListType</td></tr>
<tr><td align=right>|</td><td>NoneType</td></tr>
<tr><td align=right>|</td><td>CallableType</td></tr>
<tr><td align=right>|</td><td>ModuleType</td></tr>
<tr><td align=right>|</td><td>ClassType</td></tr>
<tr><td align=right>|</td><td>TypeType</td></tr>
<tr><td align=right>|</td><td>OtherType</td></tr>
<tr><td colspan=2>
The type representing the range of types available to python programs.
Values of this type are provided by the pytype function, and identify the
python type of opaque pyobject objects.
</td></tr></table>

<h3>Supported Functions from the Python/C API</h3>
In each case, the signature of the function is unchanged from the Python/C
API except for the case of 'out' pointer to pointer parameters; 
in the case of a single return, the returned value is copied, otherwise, 
a tuple is created with copies of all output parameters.  In the case of
zero parameter, or void return, unit is used.<p>
In python API functions that take a FILE *, an int file descriptor is used
instead such as those returned by the Unix library.<p>

<h4>fun unit -> unit</h4>
py_initialize, py_finalize, pyerr_print, pyerr_clear, pyimport_cleanup
<h4>fun int -> unit</h4>
py_exit, pyerr_printex
<h4>fun string -> unit</h4>
py_setprogramname, py_setpythonhome
<h4>fun unit -> int</h4>
py_isinitialized, pyeval_getrestricted
<h4>fun string -> int</h4>
pyrun_simplestring, pyimport_importfrozenmodule,
<h4>fun (int * string) -> int</h4>
pyrun_anyfile, pyrun_simplefile, pyrun_interactiveone, pyrun_interactiveloop,
py_fdisinteractive
<h4>fun (int * string * int) -> int</h4>
pyrun_anyfileex, pyrun_simplefileex
<h4>fun unit -> string</h4>
py_getprogramname, py_getpthonhome, py_getprogramfullpath, py_getprefix,
py_getexecprefix, py_getpath, py_getversion, py_getplatform, py_getcopyright,
py_getcompiler, py_getbuildinfo
<h4>fun (string * int * pyobject * pyobject) -> pyobject</h4>
pyrun_string
<h4>fun (int * string * int * pyobject * pyobject) -> pyobject</h4>
pyrun_file
<h4>fun (int * string * int * pyobject * pyobject * int) -> pyobject</h4>
pyrun_fileex
<h4>fun (string * string * int) -> pyobject</h4>
py_compilestring
<h4>fun (pyobject * int * int) -> int</h4>
pyobject_print, pytuple_getslice, pysequence_getslice</h4>
<h4>fun pyobject -> pyobject</h4>
pyobject_repr, pyobject_str, pyobject_unicode, pydict_keys, pydict_values,
pydict_items, pydict_copy, pymodule_getdict, pymethod_function, pymethod_self,
pymethod_class, pymodule_getdict, pyimport_reloadmodule, pyobject_type, 
pynumber_negative, pynumber_positive, pynumber_absolute, pynumber_invert,
pynumber_int, pynumber_long, pynumber_float, pysequence_tuple, pysequence_list
<h4>fun (pyobject * pyobject * int) -> pyobject</h4>
pyobject_richcompare
<h4>fun (pyobject * string) -> pyobject</h4>
pyobject_getattrstring, pydict_getitemstring, pysequence_fast, 
pymapping_haskeystring, pymapping_getitemstring
<h4>fun (pyobject * pyobject) -> pyobject</h4>
pyobject_getattr, pystring_format, pydict_getitem, pyinstance_newraw, 
pyeval_callobject, pyobject_getitem, pyobject_delitem, pynumber_add,
pynumber_subtract, pynumber_multiply, pynumber_divide, pynumber_remainder,
pynumber_divmod, pynumber_lshift, pynumber_rshift, pynumber_and, pynumber_xor,
pynumber_or, pynumber_inplaceadd, pynumber_inplacesubtract, pynumber_inplacemultiply, pynumber_inplacedivide, pynumber_inplaceremainder, pynumber_inplacelshift, pynumber_inplacershift, pynumber_inplaceand, pynumber_inplacexor, pynumber_inplaceor, pysequence_concat, pysequence_inplaceconcat
<h4>fun pyobject -> int</h4>
pyobject_istrue, pyobject_not, pycalable_check, pystring_size, pydict_size,
pytuple_new, pyerr_exceptionmatches, pyobject_size, pynumber_check, 
pysequence_check, pysequence_size, pysequence_length, pymapping_check,
pymapping_size, pymapping_length, pyint_asint
<h4>fun (pyobject * pyobject) -> int</h4>
pyobject_compare, pyobject_hasattr, pydict_delitem, 
pyerr_givenexceptionmatches, pysequence_count, pysequence_contains, 
pysequence_in, pysequence_index, pymapping_haskey
<h4>fun (pyobject * pyobject * int) -> int</h4>
pyobject_richcomparebool, pysequence_delitem
<h4>fun (pyobject * string * pyobject) -> int</h4>
pyobject_setattrstring, pydict_setitemstring
<h4>fun (pyobject * string) -> int</h4>
pyobject_hasattrstring, pydict_delitemstring, pysequence_inplacerepeat
<h4>fun (pyobject * pyobject) -> (pyobject * pyobject)</h4>
pynumber_coerce, pynumber_coerceex
<h4>fun (pyobject * pyobject * pyobject) -> int</h4>
pyobject_setattr, pydict_setitem, pyobject_setitem
<h4>fun pyobject -> int64</h4>
pyobject_hash, pyint_aslong
<h4>fun pyobject -> string</h4>
pystring_asstring, pymodule_getname, pymodule_getfilename
<h4>fun (pyobject * pyobject) -> pyobject</h4>
pystring_concat, pystring_concatanddel
<h4>fun string -> pyobject</h4>
pystring_fromstring, pymodule_new, pyimport_addmodule, pyimport_importmodule,
pyimport_import
<h4>fun unit -> pyobject</h4>
pydict_new, pyerr_occurred, pyimport_getmoduledict, pyeval_getbuiltins,
pyeval_getglobals, pyeval_getlocals, pyeval_getframe
<h4>fun pyobject -> unit</h4>
pydict_clear, pyerr_setnone
<h4>fun (pyobject * int) -> (pyobject * pyobject * int)</h4>
pydict_next
<h4>fun int64 -> pyobject</h4>
pyint_fromlong
<h4>fun unit -> int64</h4>
pyint_getmax
<h4>fun float -> pyobject</h4>
pyfloat_fromdouble
<h4>fun pyobject -> float</h4>
pyfloat_asdouble
<h4>fun int -> pyobject</h4>
pytuple_new, pyint_fromint
<h4>fun (pyobject * int) -> pyobject</h4>
pytuple_getitem, pysequence_repeat, pysequence_getitem
<h4>fun (pyobject * int * pyobject) -> int</h4>
pytuple_setitem, pysequence_setitem, pymapping_setitem
<h4>fun (pyobject * pyobject * pyobject) -> pyobject</h4>
pyslice_new, pyclass_new, pyinstance_new, pymethod_new, 
pyeval_callobjectwithkeywords, pynumber_power, pynumber_inplacepower
<h4>fun (pyobject * int) -> (int * int * int)</h4>
pyslice_getindices
<h4>fun (int * int * int * int) -> pyobject</h4>
pyrange_new
<h4>fun (pyobject * pyobject) -> unit</h4>
pyerr_setobject
<h4>fun (pyobject * string) -> unit</h4>
pyerr_setstring
<h4>fun (pyobject * pyobject * pyobject) -> (pyobject * pyobject * pyobject)</h4>
pyerr_fetch, pyerr_normalizeexception
<h4>fun (pyobject * pyobject * pyobject) -> unit</h4>
pyerr_restore
<h4>fun (pyobject * string) -> pyobject</h4>
pyimport_execcodemodule
<h4>fun (string * pyobject * string) -> pyobject</h4>
pyimport_execcodemoduleex
<h4>fun (string * pyobject * pyobject * pyobject) -> pyobject</h4>
pyimport_importmoduleex
<h4>fun pyobject -> string</h4>
pyobject_ascharbuffer, pyobject_asreadbuffer, pyobject_aswritebuffer
<h4>fun (pyobject * int * int * pyobject) -> int</h4>
pysequence_setslice
<h4>fun (pyobject * int * int) -> int</h4>
pysequence_delslice

<h3>Unique Functions Needed for Ocaml</h3>
In addition to the functions in the usual library, several new functions are
provided which give specific support for ocaml.<p>

<table border=0 width=100%>
<tr bgcolor="#c0c0c0">
<td><b>pytuple_toarray</b></td>
<td>pyobject -> pyobject array</td></tr>
<tr><td colspan=2>
Convert a python tuple to an ocaml array containing the same items.
</td></tr>
<tr bgcolor="#c0c0c0">
<td><b>pywrap_closure</b></td><td>(pyobject -> pyobject) -> pyobject</td></tr>
<tr><td colspan=2>
Create a python callable object from a closure.  The closure receives the
argument tuple from the invocation and returns a pyobject.
</td></tr>
<tr bgcolor="#c0c0c0">
<td><b>pywrap_value</b></td><td>'a -> pyobject</td></tr>
<tr><td colspan=2>
Create a simple void * style wrapping around an ocaml object.  The object
may be retrieved with <tt>pyunwrap_value : pyobject -> 'a</tt>.  Use this
to enclose an ocaml data structure in python to be used later.
</td></tr>
<tr bgcolor="#c0c0c0">
<td><b>pynull</b></td><td>unit -> pyobject</td></tr>
<tr><td colspan=2>
Generate the null PyObject * and return it.  This may sound dangerous, but
it is used by library calls to indicate errors to the python system.
</td></tr>
<tr bgcolor="#c0c0c0">
<td><b>pynone</b></td><td>unit -> pyobject</td></tr>
<tr><td colspan=2>
Generate a reference to the Py_None object.
</td></tr>
<tr bgcolor="#c0c0c0">
<td><b>pytuple_fromarray</b></td>
<td>pyobject array -> pyobject</td></tr>
<tr><td colspan=2>
Create a pytuple (as would be used for a function call) from the given
array.  This may be used to implement varargs calls on python functions,
and for other purposes.
</td></tr>
<tr bgcolor="#c0c0c0">
<td><b>pytuple_empty</b></td>
<td>pyobject array -> pyobject</td></tr>
<tr><td colspan=2>
Shortcut for <tt>pytuple_new 0</tt>
</td></tr>

<tr bgcolor="#c0c0c0">
<td><b>pytuple_fromsingle</b></td>
<td>pyobject -> pyobject</tt></td></tr>
<tr><td colspan=2>
Create a tuple with the single given object inside.  Use this to create
single element tuples as for a function call with one argument.
</td></tr>

<tr bgcolor="#c0c0c0">
<td><b>pytuple<i>1-5</i></b></td>
<td>(pyobject * ...) -> pyobject</tt></td></tr>
<tr><td colspan=2>
Create a python tuple that has the same contents as the given ocaml tuple.
</td></tr>

<tr bgcolor="#c0c0c0">
<td><b>pytype</b></td>
<td>pyobject -> pyobject_type</tt></td></tr>
<tr><td colspan=2>
Determine roughly which type family the given value belongs to.  For example,
<tt>pytype (pystring_fromstring "hi")</tt> yields <tt>StringType</tt>.
</td></tr>
</table>

<h3>Sample Application</h3>
This is the sample application that I developed the library with.  It 
illustrates a python function call, as well as a call back into ocaml.
The first form is used in cases where python libraries are to be used
from ocaml, and the second would be used to produce native libraries in
ocaml.<p>

<pre>
open Pycaml ;;

let colorsys = pyimport_importmodule "colorsys"
let dict = pymodule_getdict colorsys

let triplet = pytuple3 (pyfloat_fromdouble 1.0,
			pyfloat_fromdouble 0.5,
			pyfloat_fromdouble 0.2) ;;

let rgbtoyiq = pydict_getitemstring (dict,"rgb_to_yiq")
let triplet = pyeval_callobject (rgbtoyiq,triplet)

let _ = print_endline ((string_of_float
			  (pyfloat_asdouble (pytuple_getitem (triplet,0)))) ^ 
		       " " ^
		       (string_of_float
			  (pyfloat_asdouble (pytuple_getitem (triplet,1)))) ^
		       " " ^
		       (string_of_float
			  (pyfloat_asdouble (pytuple_getitem (triplet,2))))) ;;

let x = pywrap_closure 
    (fun x -> print_string (pystring_asstring (pytuple_getitem (x,0))) ; 
      pynone ())

let _ = pyeval_callobject 
    (x,pytuple_fromsingle (pystring_fromstring "hi there"))
</pre>
</body>
</html>
Commit	Line	Data
34e49164 C	1	<html>
	2	<head>
	3	<title>Module Pycaml</title>
	4	</head>
	5	<body>
	6	<table border=0 width="100%"><tr><td bgcolor="#c0c0c0">
	7	<h1>Pycaml</h1>
	8	</td></tr></table>
	9	<p>
	10	<h2>What is Pycaml</h2>
	11	A library written by <a href=mailto:arty@users.sourceforge.net>
	12	arty@users.sourceforge.net</a> which follows the Python/C API as
	13	closely as possible, while
	14	providing equivalent functionality for objective caml. This is built
	15	against python 2.x and Ocaml 3.04.<p> It is intended to allow users to
	16	build native ocaml libraries and use them from python, and alternately,
	17	in order to allow ocaml users to benefit from linkable libraries provided
	18	for python.<p>
	19	I created this library in order to take advantage of python binding for
	20	certain native libraries from ocaml. While it is true that I could have
	21	written new interfaces specifically for ocaml, the python interface is
	22	sufficient for my needs, and this project was easier.<p>
	23
	24	<b>Note:</b> Unfortunately, the symbol <tt>init_exceptions</tt> exists in
	25	both compiled ocaml code, and the python runtime. In order to proceed, you
	26	must rename this symbol either in the ocaml distribution (in byterun/fail.c,
	27	and byterun/startup.c), or in the python distribution, and rebuild the
	28	software appropriately.<p>
	29
	30	Please edit the <tt>Makefile</tt> to put in your system's libraries used for
	31	compiling programs embedded with python. This library compiles on most
	32	linux boxes without modification. The python interpreter is used to determine
	33	the path to the python library and must be in your path when you run make.
	34	<p>
	35
	36	<b>Get the distribution here:</b><a href=pycaml.tar.gz>pycaml.tar.gz</a><p>
	37
	38	Because these are made to closely mirror the python API, the user should
	39	become familiar with the python API.<p>
	40	Given Ocaml parameter passing convention, it was convenient to pass multiple
	41	arguments as members of a tuple, but single arguments without. Consequently,
	42	functions with arity 1, such as pytuple_new are called as<p>
	43	<pre>
	44	pytuple_new 3 ;;
	45	</pre><p>
	46	And functions with more arguments are called as<p>
	47	<pre>
	48	pydict_getitemstring (dict,"keystring") ;;
	49	</pre>
	50
	51	<h2>Module Pycaml</h2>
	52
	53	<h3>Visible Types</h3>
	54
	55	<table border=0>
	56	<tr bgcolor="#c0c0c0"><td>type</td><td width="100%">pyobject</td></tr>
	57	<tr><td colspan=2>
	58	The abstract type of python objects.
	59	</td></tr>
	60	<tr bgcolor="#c0c0c0"><td>type</td><td>pyobject_type =</td></tr>
	61	<tr><td align=right></td><td>TupleType</td></tr>
	62	<tr><td align=right>\|</td><td>StringType</td></tr>
	63	<tr><td align=right>\|</td><td>IntType</td></tr>
	64	<tr><td align=right>\|</td><td>FloatType</td></tr>
65	<tr><td align=right>\|</td><td>ListType</td></tr>
66	<tr><td align=right>\|</td><td>NoneType</td></tr>
67	<tr><td align=right>\|</td><td>CallableType</td></tr>
68	<tr><td align=right>\|</td><td>ModuleType</td></tr>
69	<tr><td align=right>\|</td><td>ClassType</td></tr>
70	<tr><td align=right>\|</td><td>TypeType</td></tr>
71	<tr><td align=right>\|</td><td>OtherType</td></tr>
72	<tr><td colspan=2>
73	The type representing the range of types available to python programs.
74	Values of this type are provided by the pytype function, and identify the
75	python type of opaque pyobject objects.
76	</td></tr></table>
77
78	<h3>Supported Functions from the Python/C API</h3>
79	In each case, the signature of the function is unchanged from the Python/C
80	API except for the case of 'out' pointer to pointer parameters;
81	in the case of a single return, the returned value is copied, otherwise,
82	a tuple is created with copies of all output parameters. In the case of
83	zero parameter, or void return, unit is used.<p>
84	In python API functions that take a FILE *, an int file descriptor is used
85	instead such as those returned by the Unix library.<p>
86
87	<h4>fun unit -> unit</h4>
88	py_initialize, py_finalize, pyerr_print, pyerr_clear, pyimport_cleanup
89	<h4>fun int -> unit</h4>
90	py_exit, pyerr_printex
91	<h4>fun string -> unit</h4>
92	py_setprogramname, py_setpythonhome
93	<h4>fun unit -> int</h4>
94	py_isinitialized, pyeval_getrestricted
95	<h4>fun string -> int</h4>
96	pyrun_simplestring, pyimport_importfrozenmodule,
97	<h4>fun (int * string) -> int</h4>
98	pyrun_anyfile, pyrun_simplefile, pyrun_interactiveone, pyrun_interactiveloop,
99	py_fdisinteractive
100	<h4>fun (int * string * int) -> int</h4>
101	pyrun_anyfileex, pyrun_simplefileex
102	<h4>fun unit -> string</h4>
103	py_getprogramname, py_getpthonhome, py_getprogramfullpath, py_getprefix,
104	py_getexecprefix, py_getpath, py_getversion, py_getplatform, py_getcopyright,
105	py_getcompiler, py_getbuildinfo
106	<h4>fun (string * int * pyobject * pyobject) -> pyobject</h4>
107	pyrun_string
108	<h4>fun (int * string * int * pyobject * pyobject) -> pyobject</h4>
109	pyrun_file
110	<h4>fun (int * string * int * pyobject * pyobject * int) -> pyobject</h4>
111	pyrun_fileex
112	<h4>fun (string * string * int) -> pyobject</h4>
113	py_compilestring
114	<h4>fun (pyobject * int * int) -> int</h4>
115	pyobject_print, pytuple_getslice, pysequence_getslice</h4>
116	<h4>fun pyobject -> pyobject</h4>
117	pyobject_repr, pyobject_str, pyobject_unicode, pydict_keys, pydict_values,
118	pydict_items, pydict_copy, pymodule_getdict, pymethod_function, pymethod_self,
119	pymethod_class, pymodule_getdict, pyimport_reloadmodule, pyobject_type,
120	pynumber_negative, pynumber_positive, pynumber_absolute, pynumber_invert,
121	pynumber_int, pynumber_long, pynumber_float, pysequence_tuple, pysequence_list
122	<h4>fun (pyobject * pyobject * int) -> pyobject</h4>
123	pyobject_richcompare
124	<h4>fun (pyobject * string) -> pyobject</h4>
125	pyobject_getattrstring, pydict_getitemstring, pysequence_fast,
126	pymapping_haskeystring, pymapping_getitemstring
127	<h4>fun (pyobject * pyobject) -> pyobject</h4>
128	pyobject_getattr, pystring_format, pydict_getitem, pyinstance_newraw,
129	pyeval_callobject, pyobject_getitem, pyobject_delitem, pynumber_add,
130	pynumber_subtract, pynumber_multiply, pynumber_divide, pynumber_remainder,
131	pynumber_divmod, pynumber_lshift, pynumber_rshift, pynumber_and, pynumber_xor,
132	pynumber_or, pynumber_inplaceadd, pynumber_inplacesubtract, pynumber_inplacemultiply, pynumber_inplacedivide, pynumber_inplaceremainder, pynumber_inplacelshift, pynumber_inplacershift, pynumber_inplaceand, pynumber_inplacexor, pynumber_inplaceor, pysequence_concat, pysequence_inplaceconcat
133	<h4>fun pyobject -> int</h4>
134	pyobject_istrue, pyobject_not, pycalable_check, pystring_size, pydict_size,
135	pytuple_new, pyerr_exceptionmatches, pyobject_size, pynumber_check,
136	pysequence_check, pysequence_size, pysequence_length, pymapping_check,
137	pymapping_size, pymapping_length, pyint_asint
138	<h4>fun (pyobject * pyobject) -> int</h4>
139	pyobject_compare, pyobject_hasattr, pydict_delitem,
140	pyerr_givenexceptionmatches, pysequence_count, pysequence_contains,
141	pysequence_in, pysequence_index, pymapping_haskey
142	<h4>fun (pyobject * pyobject * int) -> int</h4>
143	pyobject_richcomparebool, pysequence_delitem
144	<h4>fun (pyobject * string * pyobject) -> int</h4>
145	pyobject_setattrstring, pydict_setitemstring
146	<h4>fun (pyobject * string) -> int</h4>
147	pyobject_hasattrstring, pydict_delitemstring, pysequence_inplacerepeat
148	<h4>fun (pyobject * pyobject) -> (pyobject * pyobject)</h4>
149	pynumber_coerce, pynumber_coerceex
150	<h4>fun (pyobject * pyobject * pyobject) -> int</h4>
151	pyobject_setattr, pydict_setitem, pyobject_setitem
152	<h4>fun pyobject -> int64</h4>
153	pyobject_hash, pyint_aslong
154	<h4>fun pyobject -> string</h4>
155	pystring_asstring, pymodule_getname, pymodule_getfilename
156	<h4>fun (pyobject * pyobject) -> pyobject</h4>
157	pystring_concat, pystring_concatanddel
158	<h4>fun string -> pyobject</h4>
159	pystring_fromstring, pymodule_new, pyimport_addmodule, pyimport_importmodule,
160	pyimport_import
161	<h4>fun unit -> pyobject</h4>
162	pydict_new, pyerr_occurred, pyimport_getmoduledict, pyeval_getbuiltins,
163	pyeval_getglobals, pyeval_getlocals, pyeval_getframe
164	<h4>fun pyobject -> unit</h4>
165	pydict_clear, pyerr_setnone
166	<h4>fun (pyobject * int) -> (pyobject * pyobject * int)</h4>
167	pydict_next
168	<h4>fun int64 -> pyobject</h4>
169	pyint_fromlong
170	<h4>fun unit -> int64</h4>
171	pyint_getmax
172	<h4>fun float -> pyobject</h4>
173	pyfloat_fromdouble
174	<h4>fun pyobject -> float</h4>
175	pyfloat_asdouble
176	<h4>fun int -> pyobject</h4>
177	pytuple_new, pyint_fromint
178	<h4>fun (pyobject * int) -> pyobject</h4>
179	pytuple_getitem, pysequence_repeat, pysequence_getitem
180	<h4>fun (pyobject * int * pyobject) -> int</h4>
181	pytuple_setitem, pysequence_setitem, pymapping_setitem
182	<h4>fun (pyobject * pyobject * pyobject) -> pyobject</h4>
183	pyslice_new, pyclass_new, pyinstance_new, pymethod_new,
184	pyeval_callobjectwithkeywords, pynumber_power, pynumber_inplacepower
185	<h4>fun (pyobject * int) -> (int * int * int)</h4>
186	pyslice_getindices
187	<h4>fun (int * int * int * int) -> pyobject</h4>
188	pyrange_new
189	<h4>fun (pyobject * pyobject) -> unit</h4>
190	pyerr_setobject
191	<h4>fun (pyobject * string) -> unit</h4>
192	pyerr_setstring
193	<h4>fun (pyobject * pyobject * pyobject) -> (pyobject * pyobject * pyobject)</h4>
194	pyerr_fetch, pyerr_normalizeexception
195	<h4>fun (pyobject * pyobject * pyobject) -> unit</h4>
196	pyerr_restore
197	<h4>fun (pyobject * string) -> pyobject</h4>
198	pyimport_execcodemodule
199	<h4>fun (string * pyobject * string) -> pyobject</h4>
200	pyimport_execcodemoduleex
201	<h4>fun (string * pyobject * pyobject * pyobject) -> pyobject</h4>
202	pyimport_importmoduleex
203	<h4>fun pyobject -> string</h4>
204	pyobject_ascharbuffer, pyobject_asreadbuffer, pyobject_aswritebuffer
205	<h4>fun (pyobject * int * int * pyobject) -> int</h4>
206	pysequence_setslice
207	<h4>fun (pyobject * int * int) -> int</h4>
208	pysequence_delslice
209
210	<h3>Unique Functions Needed for Ocaml</h3>
211	In addition to the functions in the usual library, several new functions are
212	provided which give specific support for ocaml.<p>
213
214	<table border=0 width=100%>
215	<tr bgcolor="#c0c0c0">
216	<td><b>pytuple_toarray</b></td>
217	<td>pyobject -> pyobject array</td></tr>
218	<tr><td colspan=2>
219	Convert a python tuple to an ocaml array containing the same items.
220	</td></tr>
221	<tr bgcolor="#c0c0c0">
222	<td><b>pywrap_closure</b></td><td>(pyobject -> pyobject) -> pyobject</td></tr>
223	<tr><td colspan=2>
224	Create a python callable object from a closure. The closure receives the
225	argument tuple from the invocation and returns a pyobject.
226	</td></tr>
227	<tr bgcolor="#c0c0c0">
228	<td><b>pywrap_value</b></td><td>'a -> pyobject</td></tr>
229	<tr><td colspan=2>
230	Create a simple void * style wrapping around an ocaml object. The object
231	may be retrieved with <tt>pyunwrap_value : pyobject -> 'a</tt>. Use this
232	to enclose an ocaml data structure in python to be used later.
233	</td></tr>
234	<tr bgcolor="#c0c0c0">
235	<td><b>pynull</b></td><td>unit -> pyobject</td></tr>
236	<tr><td colspan=2>
237	Generate the null PyObject * and return it. This may sound dangerous, but
238	it is used by library calls to indicate errors to the python system.
239	</td></tr>
240	<tr bgcolor="#c0c0c0">
241	<td><b>pynone</b></td><td>unit -> pyobject</td></tr>
242	<tr><td colspan=2>
243	Generate a reference to the Py_None object.
244	</td></tr>
245	<tr bgcolor="#c0c0c0">
246	<td><b>pytuple_fromarray</b></td>
247	<td>pyobject array -> pyobject</td></tr>
248	<tr><td colspan=2>
249	Create a pytuple (as would be used for a function call) from the given
250	array. This may be used to implement varargs calls on python functions,
251	and for other purposes.
252	</td></tr>
253	<tr bgcolor="#c0c0c0">
254	<td><b>pytuple_empty</b></td>
255	<td>pyobject array -> pyobject</td></tr>
256	<tr><td colspan=2>
257	Shortcut for <tt>pytuple_new 0</tt>
258	</td></tr>
259
260	<tr bgcolor="#c0c0c0">
261	<td><b>pytuple_fromsingle</b></td>
262	<td>pyobject -> pyobject</tt></td></tr>
263	<tr><td colspan=2>
264	Create a tuple with the single given object inside. Use this to create
265	single element tuples as for a function call with one argument.
266	</td></tr>
267
268	<tr bgcolor="#c0c0c0">
269	<td><b>pytuple<i>1-5</i></b></td>
270	<td>(pyobject * ...) -> pyobject</tt></td></tr>
271	<tr><td colspan=2>
272	Create a python tuple that has the same contents as the given ocaml tuple.
273	</td></tr>
274
275	<tr bgcolor="#c0c0c0">
276	<td><b>pytype</b></td>
277	<td>pyobject -> pyobject_type</tt></td></tr>
278	<tr><td colspan=2>
279	Determine roughly which type family the given value belongs to. For example,
280	<tt>pytype (pystring_fromstring "hi")</tt> yields <tt>StringType</tt>.
281	</td></tr>
282	</table>
283
284	<h3>Sample Application</h3>
285	This is the sample application that I developed the library with. It
286	illustrates a python function call, as well as a call back into ocaml.
287	The first form is used in cases where python libraries are to be used
288	from ocaml, and the second would be used to produce native libraries in
289	ocaml.<p>
290
291	<pre>
292	open Pycaml ;;
293
294	let colorsys = pyimport_importmodule "colorsys"
295	let dict = pymodule_getdict colorsys
296
297	let triplet = pytuple3 (pyfloat_fromdouble 1.0,
298	pyfloat_fromdouble 0.5,
299	pyfloat_fromdouble 0.2) ;;
300
301	let rgbtoyiq = pydict_getitemstring (dict,"rgb_to_yiq")
302	let triplet = pyeval_callobject (rgbtoyiq,triplet)
303
304	let _ = print_endline ((string_of_float
305	(pyfloat_asdouble (pytuple_getitem (triplet,0)))) ^
306	" " ^
307	(string_of_float
308	(pyfloat_asdouble (pytuple_getitem (triplet,1)))) ^
309	" " ^
310	(string_of_float
311	(pyfloat_asdouble (pytuple_getitem (triplet,2))))) ;;
312
313	let x = pywrap_closure
314	(fun x -> print_string (pystring_asstring (pytuple_getitem (x,0))) ;
315	pynone ())
316
317	let _ = pyeval_callobject
318	(x,pytuple_fromsingle (pystring_fromstring "hi there"))
319	</pre>
320	</body>
321	</html>