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
Made by Loupe