Interactive LET Query: LET ECHO
The LET ECHO facility shows how FOCUS interprets FOCUS
statements. This facility is a diagnostic tool you can use when
statements containing LET-defined words are not being interpreted
the way you expect them to.
When the LET ECHO facility is activated, when you enter a FOCUS
statement, LET ECHO displays the statement as interpreted by FOCUS.
x
Syntax: How to Activate the LET ECHO Facility
To
activate the LET ECHO facility, issue the command:
LET ECHO
x
Syntax: How to Deactivate the LET ECHO Facility
ENDECHO
x
Reference: Results of LET ECHO Commands
The
following explains the results of a LET ECHO command:
- If you enter
a statement containing no LET-defined words, LET ECHO displays the
statement as you entered it.
- If you enter
a statement containing LET-defined words, LET ECHO displays the statement
with the substitutions made.
- If the statement
contains variable substitutions, LET ECHO displays the substitutions
with the placeholders filled in.
- If the statement
contains multiple-line substitutions, LET ECHO displays the statement
with the substitutions on multiple lines.
- If the statement
contains null substitutions, LET ECHO displays the statement with the
LET-defined words deleted.
- If the statement
contains recursive substitutions, the substitutions appear as they are
finally resolved.
- LET ECHO may
be coded as the first line of a FOCEXEC and ENDECHO as the last line.
Note: If
you enter a statement containing a variable substitution, you must enter
as many words after the LET-defined word as there are placeholders
in the phrase; otherwise, LET ECHO will wait for additional input.