ON...GOSUB
(Statement)
Call a subroutine depending upon the value of an expression.
ON <expression> GOSUB <labelname>[,<labelname>]...
This statement transfers control to the subroutine beginning with the "nth" <labelname> depending upon the value "n" of <expression>. These <labelname>s are counted, starting from left to right.
If the value of <expression> is real, the system truncates it to an integer "n."
If the operation result of <expression> exceeds the number of <labelname>s, this statement produces nothing.
Use a RETURN statement to return control from the subroutine called by GOSUB (ON...GOSUB) to the caller program.
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REM Evaluate more than one condition
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SELECT CASE Index
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'If the index value and the CASE statement value match,
'the command executes
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CASE 0
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'If the index is 0
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STOP
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'Stop program execution
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CASE 1
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'If the index is 1
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HALT "STOP"
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'Stop program execution
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CASE 2
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'If the index is 2
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HOLD "STOP"
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'Stop program execution temporarily
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CASE 3
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'If the index is 3
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STOPEND
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'Cycle-stop a continuously executed program
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CASE 4
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'If the index is 4
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ON li1 + li2 GOSUB *samp1, *samp2, *samp3
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'Call a subroutine beginning with the nth labelname
'depending upon the value n of li1+li2
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CASE 5
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'If the index is 5
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ON li1 + li2 GOTO *samp1, *samp2, *samp3
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'Jump to the nth label depending upon the value n of li1+li2
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CASE 6
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'If the index is 6
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END
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'Declare the end of motion executed by the program
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END SELECT
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'Declare the end of conditions evaluation statement
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