Python::PythonProgram Class Reference

Program for embedding and executing Python code. More...

Public Member Methods
	aliasDefinition (string python_source_path, string python_target_path)
	Creates an alias in the Python program for the given symbol. More...
auto	callFunction (string func_name,...)
	Call the given function and return the result. More...
auto	callFunctionArgs (string func_name, *softlist< auto > argv)
	Call the given function and return the result. More...
auto	callMethod (string class_name, string method_name,...)
	Call the given method and return the result. More...
auto	callMethodArgs (string class_name, string method_name, *softlist< auto > argv)
	Call the given method and return the result. More...
	constructor (string source_code, string source_label)
	Creates the object and parses and runs the given source code. More...
	destructor ()
	Destroys the interpreter context and invalidates the object.
auto	evalExpression (string source_code, string source_label="exp")
	Parse, compile, and evaluate the given expression and return any result. More...
auto	evalStatement (string source_code, string source_label="stmt")
	Parse, compile, and evaluate the given statement and return any result; declarations are not persistent. More...
auto	evalStatementKeep (string source_code, string source_label="stmt")
	Parse, compile, and evaluate the given statement and return any result; declarations are persistent. More...
	importNamespace (string qore_ns_path, string py_module_path)
	Imports the given Qore namespace to the Python program object under the given module path. More...
auto	run ()
	Runs the program. More...
	setSaveObjectCallback (*code save_object_callback)
	Sets the "save object" callback for Qore objects created from Python code. More...

Static Public Member Methods
static auto	evalExpression (string source_code, string source_label="exp")
	Parse, compile, and evaluate the given expression and return any result. More...
static auto	evalStatement (string source_code, string source_label="stmt")
	Parse, compile, and evaluate one or more Python statements and return any result. More...
static auto	evalStatementKeep (string source_code, string source_label="stmt")
	Parse, compile, and evaluate the given code and leave declarations in the Python program object. More...
static	setSaveObjectCallback (*code save_object_callback)
	Sets the "save object" callback for Qore objects created from Python code in the root Qore Program context. More...

Detailed Description

Program for embedding and executing Python code.

Restrictions:

Qore::PO_NO_EMBEDDED_LOGIC

Member Function Documentation

aliasDefinition()

Python::PythonProgram::aliasDefinition	(	string	python_source_path,
		string	python_target_path
	)

Creates an alias in the Python program for the given symbol.

Parameters

python_source_path	the dotted path to the source definition (ex: "some.path.to.sometehing")
python_target_path	the dotted path to the target definition (ex: "a.different.path")

Exceptions

PYTHON-ALIAS-ERROR

there was an error finding the source object or creating the target

callFunction()

auto Python::PythonProgram::callFunction	(	string	func_name,
			...
	)

Call the given function and return the result.

Parameters

func_name	the function name to call
...	arguments to the function should follow the name converted to Python values as per Type Conversions From Qore To Python

Returns

the return value of the Python function converted to Qore as per Type Conversions From Python to Qore

Exceptions

NO-FUNCTION

the given function cannot be found in the Python program's module dictionary

See also

Python Exception Handling

callFunctionArgs()

auto Python::PythonProgram::callFunctionArgs	(	string	func_name,
		*softlist< auto >	argv
	)

Call the given function and return the result.

Parameters

func_name	the function name to call
argv	arguments to the function as a list converted to Python values as per Type Conversions From Qore To Python

Returns

the return value of the Python function converted to Qore as per Type Conversions From Python to Qore

Exceptions

NO-FUNCTION

the given function cannot be found in the Python program's module dictionary

See also

Python Exception Handling

callMethod()

auto Python::PythonProgram::callMethod	(	string	class_name,
		string	method_name,
			...
	)

Call the given method and return the result.

Parameters

class_name	the name of the class implementing the method to call
method_name	the method to call
...	arguments to the method should follow the name converted to Python values as per Type Conversions From Qore To Python

Returns

the return value of the Python method call converted to Qore as per Type Conversions From Python to Qore

Exceptions

NO-CLASS	the given class cannot be found in the Python program's module dictionary
NO-METHOD	the given method cannot be found in the class

See also

Python Exception Handling

callMethodArgs()

auto Python::PythonProgram::callMethodArgs	(	string	class_name,
		string	method_name,
		*softlist< auto >	argv
	)

Call the given method and return the result.

Parameters

class_name	the name of the class implementing the method to call
method_name	the method to call
argv	arguments to the method as a list converted to Python values as per Type Conversions From Qore To Python

Returns

the return value of the Python method call converted to Qore as per Type Conversions From Python to Qore

Exceptions

NO-CLASS	the given class cannot be found in the Python program's module dictionary
NO-METHOD	the given method cannot be found in the class

See also

Python Exception Handling

constructor()

Python::PythonProgram::constructor	(	string	source_code,
		string	source_label
	)

Creates the object and parses and runs the given source code.

Parameters

source_code	the Python source to parse and compile
source_label	the label or file name of the source; this is used as the module name for the compiled Python code as well

Note

• The code is executed after parsing and compiling
• Exceptions parsing, compiling, or running the Python code are thrown according to Python Exception Handling

evalExpression() [1/2]

auto Python::PythonProgram::evalExpression	(	string	source_code,
		string	source_label = "exp"
	)

Parse, compile, and evaluate the given expression and return any result.

Parameters

source_code	the Python source to parse and compile
source_label	the label or file name of the source

Exceptions

PYTHON-COMPILE-ERROR

error parsing or compiling the given source

Note

This method uses a shared static PythonProgram object to parse, compile, and evaluate the input string

evalExpression() [2/2]

static auto Python::PythonProgram::evalExpression ( string  source_code, string  source_label = "exp"  )

static

Parse, compile, and evaluate the given expression and return any result.

Parameters

source_code	the Python source to parse and compile
source_label	the label or file name of the source

Exceptions

PYTHON-COMPILE-ERROR

error parsing or compiling the given source

Note

This method uses a shared static PythonProgram object to parse, compile, and evaluate the input string

evalStatement() [1/2]

auto Python::PythonProgram::evalStatement	(	string	source_code,
		string	source_label = "stmt"
	)

Parse, compile, and evaluate the given statement and return any result; declarations are not persistent.

Parameters

source_code	the Python source to parse and compile
source_label	the label or file name of the source

Exceptions

PYTHON-COMPILE-ERROR

error parsing or compiling the given source

See also

evalStatementKeep()

evalStatement() [2/2]

static auto Python::PythonProgram::evalStatement ( string  source_code, string  source_label = "stmt"  )

static

Parse, compile, and evaluate one or more Python statements and return any result.

Parameters

source_code	the Python source to parse and compile
source_label	the label or file name of the source

Exceptions

PYTHON-COMPILE-ERROR

error parsing or compiling the given source

Note

• This method uses the PythonProgram context in the current program to parse, compile, and evaluate the input string
• Is parsed in a "standalone" mode without being able to access existing symbols in the program

See also

evalStatementKeep()

evalStatementKeep() [1/2]

auto Python::PythonProgram::evalStatementKeep	(	string	source_code,
		string	source_label = "stmt"
	)

Parse, compile, and evaluate the given statement and return any result; declarations are persistent.

Parameters

source_code	the Python source to parse and compile
source_label	the label or file name of the source

Exceptions

PYTHON-COMPILE-ERROR

error parsing or compiling the given source

See also

evalStatement()

evalStatementKeep() [2/2]

static auto Python::PythonProgram::evalStatementKeep ( string  source_code, string  source_label = "stmt"  )

static

Parse, compile, and evaluate the given code and leave declarations in the Python program object.

Parameters

source_code	the Python source to parse and compile
source_label	the label or file name of the source

Exceptions

PYTHON-COMPILE-ERROR

error parsing or compiling the given source

Note

This method uses the PythonProgram context in the current program to parse, compile, and evaluate the input string

See also

evalStatement()

importNamespace()

Python::PythonProgram::importNamespace	(	string	qore_ns_path,
		string	py_module_path
	)

Imports the given Qore namespace to the Python program object under the given module path.

Parameters

qore_ns_path	the path to the Qore namespace (ex: "::Qore::Thread")
py_module_path	the dot-separated path to the target Python module to be created (ex: "qore.qore.thread")

Exceptions

IMPORT-NS-ERROR

Qore namespace could not be found or the root namespace was given for import

run()

auto Python::PythonProgram::run

(

)

Runs the program.

Note

Exceptions parsing or compiling the Python code are thrown according to Python Exception Handling

setSaveObjectCallback() [1/2]

Python::PythonProgram::setSaveObjectCallback

(

*code

save_object_callback

)

Sets the "save object" callback for Qore objects created from Python code.

Restrictions:

Qore::PO_NO_PROCESS_CONTROL

Example:

hash<string, object> object_cache;
code callback = sub (object obj) {
    # save object in object cache, so it doesn't go out of scope
    object_cache{obj.uniqueHash()} = obj;
}
pypgm.setSaveObjectCallback(callback);

Parameters

save_object_callback

the callback to save any Qore objects created in Python code, must take an argument of type object

Due to the differences in garbage collection approaches between Qore and Python, Qore objects must be managed with a deterministic life cycle; JaPythona objects have only weak references to Qore objects due to the lack of destructors in Python and the lack of determinism in the Python runtime for object lifecycle management.

The callback set here will be called any time a Qore object is created from Python code; if no callback is set, then the standard thread-local implementation is used where Qore objects are saved in a thread-local hash.

See also

Managing the Lifecycle of Qore objects from Python for more information

setSaveObjectCallback() [2/2]

static Python::PythonProgram::setSaveObjectCallback ( *code  save_object_callback )

static

Sets the "save object" callback for Qore objects created from Python code in the root Qore Program context.

Restrictions:

Qore::PO_NO_PROCESS_CONTROL

Example:

hash<string, object> object_cache;
code callback = sub (object obj) {
    # save object in object cache, so it doesn't go out of scope
    object_cache{obj.uniqueHash()} = obj;
}
PythonProgram::setSaveObjectCallback(callback);

Parameters

save_object_callback

the callback to save any Qore objects created in Python code, must take an argument of type object

Due to the differences in garbage collection approaches between Qore and Python, Qore objects must be managed with a deterministic life cycle; JaPythona objects have only weak references to Qore objects due to the lack of destructors in Python and the lack of determinism in the Python runtime for object lifecycle management.

The callback set here will be called any time a Qore object is created from Python code; if no callback is set, then the standard thread-local implementation is used where Qore objects are saved in a thread-local hash.

See also

Managing the Lifecycle of Qore objects from Python for more information

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The documentation for this class was generated from the following file:

• QC_PythonProgram.dox.h