%output statement (SDL script)
This topic applies to TDK SDL script extensions. For more information, see
Overview of SDL script extensions for TDK (SDL script).
SDL Script Extensions for TDK:
%string AString = "Some value"
%output AString $ AString is cleared before %outputting (no %append)
$ Note here an implicit %pushindent 0 is executed, followed by a %indent 0
... block of code that generates something...
$ Here an implicit %popindent is executed
%endoutput
%output %append AString $ AString is appended with the new value
$ Implicit %pushindent 0 and %indent 0 as above
... block of code that generates something...
$ Implicit %popindent
%endoutput
%output %keepindent AString $ AString is cleared before %outputting (no %append)
$ No %pushindent 0/%indent 0 executed due to %keepindent
... block of code that generates something...
$ No %popindent executed here (%keepindent)
%endoutput
The %output statement works exactly like a %file statement, but generated output between %output and %endoutput are written to the string specified as %output argument. %output can write to a member property as well, for example, %output Self->MyProp.
The optional %append clause appends output contents to the given string (default is flushing the string contents when the %output statement is executed).
There is no limitation on what the code block between %output and %endoutput can contain: loops, %load and operation calls are allowed (exactly like a %file statement situation).
The following example captures the operation implementation from all the model classes reusing the OperationImpl.sdl module, then appends a comment, then appends a module footer by calling some operation. In the end, the string is printed to a file:
%localstring A
%output "A"
%for %search ("", "Class")
%load "OperationImpl.sdl"
%endfor
%endoutput
$Append a comment
A = A & "\n// This is a comment\n"
$Append a footer
%output %append "A"
GenerateFooter ()
%endoutput
%file "OutputFile.cpp"
A
%endfile
By default, %output executes an implicit %pushindent 0 followed by a %indent 0. This is consistent with subsequent use of the generated string in other %output or %file statements, in such a way the indent settings of the second %output is not summed with the previous. For example:
%indent 1
%output X
"if (A < B) {\n"
%pushindent 1
"A = B;\n"
%popindent
"}\n"
"return A;\n"
%endoutput
%output Y
"int SelectGreater (int A, int B) {\n"
%pushindent 1
X $ outputs the value captured with previous %output
%popindent
"}\n"
%endoutput
$ Here the %indent level is still 1
%file "MyFile.cpp"
Y
%endfile
The above generates the following:
int SelectGreater (int A, int B) {
if (A < B) {
A = B;
}
return A;
}
Note the initial indent level (1) is ineffective on both %output statements, which restart with a 0 indent. Also note this behavior is consistent: if the %output statements did not reset the indent, the result would have been as follows:
int SelectGreater (int A, int B) {
if (A < B) {
A = B;
}
return A;
}
This because the X block would have been indented twice (at first %output statement, then at second %output statement when the whole X is %outputted again).