Functions

Chopper FUB

Combines ChopCompile and ChopRender to a single call in FUB format.

Direction	Name	Type	Description
In	pTemplate	Chop_Template_typ*	Where compiled data is stored
In	pDest	STRING*	Pointer to destination where rendered string is written to
In	destSize	STRING	Name of PV without task name to be used as action
In	pSource	STRING	Name of PV to be used for parameters
In	recompile	BOOL	Force a compile
Out	renderLength	UDINT	Length of last render
Out	status	DINT	Status of last fub call. Refer to status_information

ChopCompile

ChopCompile does a compile from pSource into pTemplate. Returns function status as DINT. Refer to status for more information. Variables in source should be surrounded by double curly braces “{{”, “}}”, and should be specified in format TaskName:VarName for local variables and VarName for global variables. Only variables declared in .var files can be used by name. For more information variable formatting see section in usage. Chopper currently supports a maximum number of variables in a source denoted by constant CHOP_TEMPLATE_MAX_VARIABLES. Note: Due to current implementation maximum number of variables is 1 less than reported by CHOP_TEMPLATE_MAX_VARIABLES.

Direction	Name	Type	Description
Out	pTemplate	Chop_Template_typ*	Template to compile into
In	pSource	STRING*	Template source to compile
Return	status	DINT	Status of compile command refer to status_information

Chopper Compiles can take an some time for larger sources. It is recommended to use caution when compiling in a fast cyclic.

variable.text:= 'Chopper';
source:= 'This is a {{var.text}} example!';
ChopCompile(ADR(template), ADR(source));

ChopRender

ChopRender does render from pTemplate into pDest. If renderLength is larger than destSize then a the pDest will end with ‘…’, followed by a null character. If pRenderLength is not 0 then it will be filled with renderLength.

Direction	Name	Type	Description
Out	pDest	STRING*	Destination to render template into
In	pTemplate	Chop_Template_typ*	Template to render
In	DestSize	UDINT	Sizeof pDest to prevent string overflow
Out	pRenderLength	UDINT*	Pointer to be populated with the string length of pDest after rendering (Optional)
Return	status	DINT	Status of render command refer to status_information

Chopper Renders are quick when using a precompiled template and are okay to use in a fast cyclic.

variable.text:= 'Chopper';
source:= 'This is a {{var.text}} example!';
ChopCompile(ADR(template), ADR(source));
ChopRender(ADR(destination), ADR(template), SIZEOF(destination), ADR(length));
// destination = 'This is a Chopper example!'
// length = 26

NOTE: Any variable that can not be found is replaced with “undefined” when rendered.

ChopReplaceVar

ChopReplaceVar replaces all pTag in pTemplate with variable specified by name in pVarName. Variable name is in format TaskName:VarName for local variables and VarName for global variables.

Direction	Name	Type	Description
In/Out	pTemplate	Chop_Template_typ*	Template to be modified
In	pTag	STRING*	Tag name to be replaced in template
In	pVarName	STRING*	Variable name to be added
Return	status	DINT	Status of last fn call refer to status_information

firstVar:= 1;
secondVar:= 2;

ChopCompile(ADR(template), ADR('My variable value is {{firstVar}}'));
ChopRender(ADR(dest), ADR(template), SIZEOF(template), ADR(renderLength)); 
//dest= 'My variable value is 1'

ChopReplaceVar(ADR(template),ADR('firstVar'),ADR('secondVar'));
ChopRender(ADR(dest), ADR(template), SIZEOF(template), ADR(renderLength));
//dest= 'My variable value is 2'

ChopReplace

ChopReplace replaces all pTag in pTemplate with a new variable. Specified by address and type. Types are specified as VAR_TYPE_enum, refer to VarTools documentation for more information.

Direction	Name	Type	Description
In/Out	pTemplate	Chop_Template_typ*	Template to be modified
In	pTag	STRING*	Tag name to be modified in template
In	address	UDINT	Variable address to be added to pTag
In	type	VAR_TYPE_enum	Variable type to be added to pTag
Return	status	DINT	Status of last fn call refer to status_information

firstVar:= 1;
secondVar:= 2;

ChopCompile(ADR(template), ADR('My variable value is {{firstVar}}'));
ChopRender(ADR(dest), ADR(template), SIZEOF(template), ADR(renderLength)); 
//dest= 'My variable value is 1'

ChopReplace(ADR(template),ADR('firstVar'),ADR(secondVar),VAR_TYPE_USINT);
ChopRender(ADR(dest), ADR(template), SIZEOF(template), ADR(renderLength));
//dest= 'My variable value is 2'

ChopGetErrorMsg

ChopGetErrorMsg retrieves text for given errorID and copies it to pDest. ChopGetErrorMsg returns a status.

Direction	Name	Type	Description
Out	pDest	STRING*	Destination to be populated
In	maxDestLength	UDINT	Max length of pDest
In	errorID	DINT	Status to get message for. See status_information
Return	status	DINT	Status of last fn call refer to status_information

ChopGetErrorMsg(ADR(msg), 50000);
// msg = Input to function is invalid