xml_obj.py¶

xml_obj.py

This file contains the objects for representing the essential TwinCAT variables and data structures found in the xml (tmc) formatted file.

Symbol¶

class pytmc.Symbol(element, base=None, suffixes=None)¶

Inherits from BaseElement

Symbol instances represent instantiated variables and DataTypes.

Parameters

element (xml.etree.ElementTree.Element) – A python xml element object connected to the intended .tmc datagroup
base (str) – The prefix that will mark pragmas intended for pytmc’s consumption.

property tc_type¶

Return the type of the data this symbol represents.

Returns: Name of data type (e.g. DINT in the case of a basic type or ‘iterator’ if it is an instance of a user defined struct/fb named ‘iterator’
Return type: str

DataType¶

class pytmc.DataType(element, base=None, suffixes=None)¶

Inherits from BaseElement

DataType instances represents the templates for uninstantiated FunctionBlocks, Enums, Structs, Unions, and Aliases.

children¶

This list contains the SubItem instances that this DataType contains. It is not recommended to set this attribute directly. Instead, set parent, which automates the setup of children for bi-directional look-up.

Type: list

Parameters

element (xml.etree.ElementTree.Element) – A python xml element object connected to the intended .tmc datagroup
base (str) – The prefix that will mark pragmas intended for pytmc’s consumption.

property datatype¶

Return the type of the data this symbol represents.

Returns: Name of data type
Return type: str

property is_enum¶

This property is true if this twincat element is an enum. It works for Datatypes, symbols and subItems.

Returns: is true if this twincat element is an enum.
Return type: Bool

property tc_extends¶

Return the DataType that this DataType is built upon

Returns: DataType name or None if there is no parent
Return type: str or None

SubItem¶

class pytmc.SubItem(element, base=None, suffixes=None, parent=None)¶

Inherits from baseElement

SubItem instances represent variables and DataTypes instantiated within DataTypes.

parent¶

This is a reference to the DataType that contains this SubItem. We reccommend setting this attribute directly instead of setting children. This property automates settting children for bi-directional look-up. The relationship can be deleted using del SubItem_instance.parent or by setting parent equal to None. To create a relationship, simply set parent equal to the intended parent.

Type: str or None

Parameters

element (xml.etree.ElementTree.Element) – A python xml element object connected to the intended .tmc datagroup
base (str) – The prefix that will mark pragmas intended for pytmc’s consumption.
parent (baseElement) – The DataStructure in which this SubItem appears

property tc_type¶

Return the type of the data this symbol represents.

Returns: Name of data type (e.g. DINT in the case of a basic type or ‘iterator’ if it is an instance of a user defined struct/fb named ‘iterator’
Return type: str

BaseElement¶

class pytmc.xml_obj.BaseElement(element, base=None, suffixes=None)¶

Base class for representing variables as they appear in the .tmc (xml) format.

Parameters

element (xml.etree.ElementTree.Element) – A python xml element object connected to the intended .tmc datagroup
base (str) – The prefix that will mark pragmas intended for pytmc’s consumption.

property has_config¶

Shortcut for determining if this element has pragmas.

Returns: True if there is a config pragma attached to this xml element
Return type: bool

property is_array¶

This property is true if this twincat element is an array.

Returns: is true if this twincat element is an array
Return type: Bool

property is_str¶

This property is true if this twincat element is a string.

Returns: is true if this twincat element is an string
Return type: Bool

property iterable_length¶

Obtain the length of an iterable type.

Returns: Return the length of the string/array if the element is a string or an array. Otherwise return None
Return type: int or None

property name¶

Return the user assigned TwinCAT variable name for this Symbol/DataType/SubItem. This info is taken from the text of the name field sub-element.

Returns: The name of the variable
Return type: str

property properties¶

Produce a dictionary of lists for the properties associated with this element. The value of the dictionary is a list allowing for multiple properties w/ the same name.

Returns: Dictionary. The key is the property name and the value is a list of values found in the xml
Return type: dict

property raw_config¶

Produce a stripped-down set of properties including only those that are recognized as pragmas intended for pytmc’s consumption.

Returns: produce the string from the pragma marked for pytmc or a None if no such pragma can be found
Return type: str or None