18. Mixing )text and )action blocks

Example 18.1:

)text out='q1'

2

4

6

)endtext

)action in='q1'

hideword = word.1

if word.1 < 6 then do

)action in='q1'

hideword "multiply by" word.1 "is "word.1 * hideword

)endaction

end

)endaction

Output is:

2 multiply by 2 is 4

2 multiply by 4 is 8

2 multiply by 6 is 12

4 multiply by 2 is 8

4 multiply by 4 is 16

4 multiply by 6 is 24

In this example it is necessary to move word.1 to the user defined variable hideword. This is done in the outer action block - to prevent overwriting of the variable when word.1 is assigned values in the inner action block during the run of the RXS program.

Notice:

• An action block may contain another action block: An action block is syntactically like any other chunk of coding in the RXS program. That is, it may be conditioned by an if-statement etc.
• An action block may reside into an action block, which may reside inside an action block - etc.
• Action blocks may contain text blocks and text blocks may contain action blocks - in any combination.
• Accordingly )trigger and )notrigger parts of an action block may contain any hierarchy of action blocks and text blocks
• General orders for an action block are executed once when execution hits the block (In the example above, the general orders for the inner action block are executed twice because the flow of execution in the RXS program will hit this action block twice)

The principle of the 'execution counter' sweeping down the program, activating line after line, top to bottom, now becomes a bit complicated: When hitting an action block inside another action block, the outer action block is halted while the inner action block is interpreted consuming its own input. When finished, the outer action block turns active again.

If an action block tries to consume a RXS queue which is not yet produced, execution ends in error (more specific rules in section 12).

 

 

Assigning variables instead of values to general orders can be relevant:

Example 33.8:

)text out='q1'

a1

a2

a3

)endtext

)action in='q1'

)action out='myqualif.mydsn('word.1')'

"What's up doc?"

)endaction

)endaction

This RXS program will create (or replace) three members, A1, A2, and A3, in the dataset 'myqualif.mydsn'. All three members will contain a line with the text "What's up doc?"