Targeted Text statements: Difference between revisions

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   %i = 3, %al(%i) = 30
   %i = 3, %al(%i) = 30
==SetText statement==
==SetText statement==
The SetText statement works much the same as AuditText, PrintText, and TraceText, but it is used to set a variable instead of outputting a string. The syntax of the SetText statement is:
The SetText statement works much the same as AuditText, PrintText, and TraceText, but it is used to set a variable instead of outputting a string. That is, its primary intent is to use the text it sets in the current program.
                     
The syntax of the SetText statement is:
   setText %variable = string
   setText %variable = string
Where:
Where:

Revision as of 22:43, 17 December 2010

The AuditText, PrintText, and TraceText statements are abbreviated forms of the Text and Html statements. They have the same effect as the Text Audit, Text Print, Text Trace, Text Return, and Text Set statements respectively.

The AuditText, PrintText, and TraceText statements are available in Sirius Mods 7.2 and later.

In addition, the SetText statement, which is available in Sirius Mods 7.8 and later, uses the same syntax as AuditText, PrintText, and TraceText to set a target variable.

The ReturnText statement, which is available in Sirius Mods 7.8 and later, uses the same syntax as AuditText, PrintText, and TraceText to return a string value from a User Language function or property Get method.

The AuditText, PrintText, and TraceText keywords are simply a merging and reordering of Text Audit, Text Print, and Text Trace to emphasize the principle action. The lone difference between the former and latter forms is that the former cannot be used if you want to include other Html/Text options, as in:

  text noexpr print The set is {2, 3, 5, 8, 13, ...}

However, as of Sirius Mods 7.8, certain Text statement directives can be placed after a tilde character (~) inside curly braces in any of the targeted text statements. For example

 setText %ls = {~nocont}---{$time}---

sets %ls to the current time embedded in hyphens. Because the ~nocont directive was specified, the terminating hyphen is not treated as a continuation character.

The tilde directives that are allowed in targeted text statements are:

~exprE
Sets the expression end characters. This directive must be followed by a space and then the expression start characters. For example, {~expre >} sets the expression end characters to a single greater-than sign (>). ~exprE can also be written as ~exprEnd. Note that the ~exprE directive must be ended by the expression end characters in effect before the ~expre directive is processed.
~exprS
Sets the expression start characters. This directive must be followed by a space and then the expression start characters. For example, {~exprs <} sets the expression start characters to a single less-than sign (<). ~exprS can also be written as ~exprStart.
~noCont
Indicates that a trailing hyphen is not treated as a continuation character. ~noCont can also be written as ~noContinuations.
~noEll
Indicates that a trailing ellipsis (...) is not treated as a partial-line indicator. Because it makes no sense to end a SetText or ReturnText with an ellipsis, this is the default for those two statements. So, while allowed, a ~noEll directive is completely unnecessary for SetText and ReturnText. ~noEll can also be written as ~noEllipses.
~noExpr
Indicates that no expressions are to be processed after the directive, and that everything after the ~noExpr directive is treated as literal text. No further tilde directives will be processed after a ~noExpr. ~noExpr can also be written as ~noExpressions.
~raw
Acts as if ~noCont, ~noEll, and ~noExpr are specified simultaneously. Note that this is slightly different from the Raw directive on the Text/Html statement, which also implies NoDum/NoDummy. Because dummy string substitution applies to lines before they are parsed, dummy string substitution would already have happened in any single-line Text statement before the ~raw directive was processed.

AuditText sends its output to the Model 204 audit trail, PrintText sends its output to the current output stream (output terminal or use dataset), and TraceText sends its output to the current trace targets. These statements are the recommended/preferred alternatives to the traditional Audit, Print, and Trace statements. They are recommended because they are more flexible and have more consistent behavior.

All text not inside curly braces in an AuditText, PrintText, or TraceText statement is considered to be literal text. For example, the following statement will display Suit the action to the word, the word to the action on the primary output stream:

  printText Suit the action to the word, the word to the action

You can place values of variables and also calculated values inside of curly braces to display the value of what is inside the braces. For example, the following would display %i = 22, %j = 33, %i * %j = 726:

  %i = 22
  %j = 33
  printText %i = {%i}, %j = {%j}, %i * %j = {%i * %j}

Any valid expression is allowed inside the curly braces, including those that contain parentheses, $functions, and method calls. For example, the following would display %i = 22, %j = 33, (%i + %j):toPower(3) = 166375:

  %i = 22
  %j = 33
  printText %i = {%i}, %j = {%j}, (%i + %j):toPower(3) = {(%i + %j):toPower(3)}

A single tilde character inside curly braces {~} must be followed (possibly with some intervening text) by an expression inside curly braces. The {~} would then be replaced with the literal contents of the following curly braces. For example, the following sequence would display %i = 22, %j = 33, (%i + %j):toPower(3) = 166375:

  %i = 22
  %j = 33
  printText {~} = {%i}, {~} = {%j}, {~} = {(%i + %j):toPower(3)}

As of Sirius Mods version 7.8, you can also use a ~= directive as a shorthand for {~}={expression}. For example,
printtext {~=%i}, {~=%j}, {~=(%i+%j):toPower(3)} would display %i=22, %j=33, (%i + %j):toPower(3)=166375.
Note that in the directive, spaces are optional after the equal sign, and the output produces no spaces before or after the equal sign. If more control of spacing is required, use the {~} directive.

One common issue with the {~} syntax is that it does not replace with its value a variable used as a subscript (perhaps for an ArrayList). For example, if you have:

  b
  %i is float
  %j is float
  %al is arraylist of float
  %al = list(13, 17, 30)
  for %i from 1 to %al:count
     printText {~} = {%al(%i)}
  end for
  end

You might expect the following to be displayed:

  %al(1) = 13
  %al(2) = 17
  %al(3) = 30

But, instead, the following is displayed:

  %al(%i) = 13
  %al(%i) = 17
  %al(%i) = 30

One way to deal with this is to "manually" build the part before the value:

  for %i from 1 to %al:count
     printText %al({%i}) = {%al(%i)}
  end for

Another way is to show the subscript value also:

  for %i from 1 to %al:count
     printText {~} = {%i}, {~} = {%al(%i)}
  end for

This displays:

  %i = 1, %al(%i) = 13
  %i = 2, %al(%i) = 17
  %i = 3, %al(%i) = 30

SetText statement

The SetText statement works much the same as AuditText, PrintText, and TraceText, but it is used to set a variable instead of outputting a string. That is, its primary intent is to use the text it sets in the current program.

The syntax of the SetText statement is:

  setText %variable = string

Where:

string
A literal string which may include expressions enclosed by curly braces, just as is used in the Text statement.

For example, the following statement sets %x to the literal string "Patriotism is the last refuge of the scoundrel". setText %x = Patriotism is the last refuge of the scoundrel And the following sets %x to the literal string "The sum of %x and %y is " followed by the sum of %x and %y: setText %x = The sum of %x and %y is {%x + %y}
%variable
A simple variable, a class variable, a class property, or a collection member (which is really just a special kind of class property).

For example, the following statement sets the String property of a StringTokenizer object to the literal string "Once upon a time": %toke is object stringTokenizer ... setText %toke:string = Once upon a time A single blank after the equal sign following a SetText is not required and is ignored, though you can use it for readability. The following statements both set %str to "Once a jolly swagman camped by a billabong". setText %str =Once a jolly swagman camped by a billabong and setText %str = Once a jolly swagman camped by a billabong Any additional blanks beyond the first one are treated as part of the literal source string.

Continuations are treated in the normal way: the text continues from the first non-blank character on the next line.
Tip: if you need to include blank characters from the next line, use {} (a null expression) to indicate the start of the continuation. For example:

  setText %str = Once a jolly swagman camped by:-
                 {}   a billabong

The statement above sets %str to:

  Once a jolly swagman camped by:   a billabong

However, since trailing blanks before a continuation are not stripped, you can also include blank characters by putting extra blanks at the end of the first SetText line:

  setText %str = Once a jolly swagman camped by:   -
                 a billabong

If you need to terminate the string with a hyphen, add the {} null expression to the end of a line. For example:

  setText %str = ------------{}

The statement above sets %str to:

  ------------

You can also use the ~noCont directive to indicate that a trailing hyphen is not to be treated as a continuation character:

  setText %str = {~nocont}------------

ReturnText statement

The ReturnText statement works much the same as AuditText, PrintText, and TraceText, but instead of outputting a string it is used to return a string value in a User Language function or property Get method. The syntax of the ReturnText statement is:

  ReturnText string

Where:

string
A literal string which may include expressions enclosed by curly braces, just as in the Text statement.

For example, if the Aphorism local function is applied to the number 1 in the following fragment, the function returns the literal string "Patriotism is the first refuge of the scoundrel":

   local function (float):aphorism is longstring
   
   if %this eq 1 then
      returnText Patriotism is the first refuge of the scoundrel
   end if
   ...
   end function

The following function returns the literal string "The sum of %x and %y is " followed by the sum of the %x and %y parameters passed to the local function:

   local function stringAdd(%x is float, %y is float)

      returnText The sum of %x and %y is {%x + %y}

   end function

Continuations are treated in the normal way: the text continues from the first non-blank character on the next line.
Tip: if you need to include blank characters from the next line, use {} (a null expression) to indicate the start of the continuation. For example:

  returnText %str = Down came a jumbuck to drink at:-
                    {}   that billabong                     

The statement above returns:

  Down came a jumbuck to drink at:   that billabong

However, since trailing blanks before a continuation are not stripped, you can also include blank characters by putting extra blanks at the end of the first ReturnText line:

  returnText %str = Down came a jumbuck to drink at:   -
                    that billabong                     

If you need to terminate the string with a hyphen, add the {} null expression to the end of a line. For example:

  returnText ------------{}

The statement above returns:

  ------------

You can also use the ~noCont directive to indicate that a trailing hyphen is not to be treated as a continuation character:

  returnText {~nocont}------------