FWD » Core Development » User Interface

When P2J displays the expressions formed by only one no-args built-in functions multiple times within the same frame are displayed only once - they behave like a field or variable.
Here is the test-set:

define variable i as int init 9.

display "num-dbs" num-dbs skip with no-labels.
display "i" i skip.
display "i + 1" i + 1 skip.
display "userid" userid skip.
display "CURRENT-LANGUAGE" CURRENT-LANGUAGE skip.
display "etime" etime skip. 
display "mtime" mtime skip.
display "lastkey" lastkey skip.
/* display guid guid skip. -- not implemented in p2j conversion */ 
display "now" now skip. 
display "today" today skip.
display "OPSYS" OPSYS skip.
display "PAGE-NUMBER" PAGE-NUMBER skip. 
display "PAGE-SIZE" PAGE-SIZE skip.
display "PROGRESS" PROGRESS skip. 
display "PROVERSION" PROVERSION skip.
display "SCREEN-LINES" SCREEN-LINES skip.
display "--------------------------------------------" skip .
display "num-dbs" num-dbs skip with no-labels.
display "i" i skip.
display "i + 1" i + 1 skip.
display "userid" userid skip.
display "CURRENT-LANGUAGE" CURRENT-LANGUAGE skip.
display "etime" etime skip. 
display "mtime" mtime skip.
display "lastkey" lastkey skip.
display "now" now skip. 
display "today" today skip.
display "OPSYS" OPSYS skip.
display "PAGE-NUMBER" PAGE-NUMBER skip. 
display "PAGE-SIZE" PAGE-SIZE skip.
display "PROGRESS" PROGRESS skip. 
display "PROVERSION" PROVERSION skip.
display "SCREEN-LINES" SCREEN-LINES skip.

The box should contain the same values up an down, but at this moment the result of following functions appear only once:
num-dbs, CURRENT-LANGUAGE, lastkey, OPSYS, PROGRESS, PROVERSION, SCREEN-LINES. Other functions might be affected.

I did not see any proof that user-defined functions and functions with at least one argument to fail when displayed multiple times.

Looking into the generated code you can clearly see that all occurrences of such displayed functions use the same widget for displaying the result of the simple expression.