ConvertBot: unconditionally transfers macro program control

2020-04-27T22:04:36Z

unconditionally transfers macro program control

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unconditionally transfers macro program control
<pre>
<name> - Name of statement label

GOTO is used in conjunction with the LABEL command to transfer the flow of
control within a macro. <label> can be any string of alphabetic characters
(including the underscore) or digits. "ABC", "THE_TOP", "100", and "123G" are
all examples of valid statement labels.

When a GOTO is encountered, the macro begins looking in the specified direction
for a LABEL command whose argument exactly matches <label>. If it never finds
such a LABEL command, it enters suspend (S-Midas) mode with an error.

COMPUTED GOTOs

Because the label matching occurs at run-time, it means that you can caret (^)
a result label for the <label> argument, and a single GOTO can reference a
number of labels depending on the value of the result. This can be useful when
you want to perform a number of alternatives depending on the value of some
result. It is usually advisable to use the "*" as the direction argument,
since you may not know at the time of writing the macro whether the run-time
destination will be above or below you. For example:

goto case^which_one

will look for LABEL CASE1 if WHICH_ONE = 1, LABEL CASE2 if WHICH_ONE = 2,
LABEL CASE523.4 if WHICH_ONE = 523.4, LABEL CASESTOP if WHICH_ONE = STOP, etc.

INTERACTIVE GOTOs

Because the GOTO is a run-time command, it can be used at the S-Midas prompt
after an error has occurred or the macro has PAUSEd. This can be very helpful
in a debugging situation.

Switches: NONE

See Also: LABEL

</pre>

[[Category:NXM_Explain]]

GOTO - Revision history

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