Difference between revisions of "BEGIN SEQUENCE"

Revision as of 10:31, 23 October 2009

Purpose

Start error-handling block

Syntax

BEGIN SEQUENCE

<command>

[BREAK]

<command>

END SEQUENCE

See Also

ON ERROR

Description

The main purpose of the BEGIN SEQUENCE ... BREAK ... END SEQUENCE construct is to allow for programmable error handling. The commands that follow the END SEQUENCE command will normally be devoted to error handling and will be executed immediately.

BREAK

The BREAK keyword can be used whenever the program commands detect an error. For this purpose, BREAK may appear at any depth within nested procedures. When BREAK is encountered, all stacked procedures will unwind automatically.

Example

error = .F.
begin sequence
 
do while not eof()
    if empty(name)
        rec = recno()
        error = .T.
        break
    else
        display name
    endif
    skip
enddo
 
end sequence
 
if error
    set message to "Error: No name in record; &rec."
else
    set message to "End of file reached."
endif

Products

Recital Database Server, Recital Mirage Server, Recital Terminal Developer