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MiniRobotLanguage (MRL)
JNZ. Conditional Jump
Jump is Not Zero
Intention
This command can be used to test a Variable for zero and Jump to a label if the variable is not zero. Here is a short example:
VAR.§§TST=-50
:try
VIC.§§TST
' just jump without other features
JNZ.§§TST|try
PRT.Hier
:over
DMP.
MBX.!
END.
Additionally the Command allows a "post-decrement" or alternatively a "post-increment" for easy Loop-Constructions. "Post-increment" will increment the given variable after the test inside the variable was done. Here is an example with "Post-increment":
VAR.§§TST=50
:try
DBP.Number is: §§TST
JNZ.§§TST<try
DBP.Hier
:over
DMP.
MBX.!
END.
The command can be switched from default mode (Jump Mode) into "Gosub Mode" if you prefix the Label-Parameter P3 with a colon. Here is an example:
' will jump to the Label "over" in Gosub-Mode
JNZ.$$NUM|:over
' we can use Labels that are in variables, too
: $$LAB=:over
JNZ.$$NUM|$$LAB
JNZ. is somehow the counterpart to JIZ. - Jump-If-Zero .
Syntax
JNZ.P1P2P3
Parameter Explanation
P1 - Must be a Variable, like $$AAA or §§BBB or $$001
P2 - increment/decrement operator or just a | .
P3 - Label or Variable that evaluates to a Label.
If it starts with a ":" (colon) a JSR. - Jump SubRoutine (Label) (GOSUB like)
Jump is done instead of the normal JMP. - Jump to Label (GOTO like) Jump..
Example
'*************************************
' JNZ - Example
'*************************************
VAR.§§TST=-50
:try
VIC.§§TST
' just jump without other features
JNZ.§§TST|try
PRT.Hier
:over
DMP.
MBX.!
END.
'*************************************
' Advanced JNZ - Example (using :Label)
' the second one makes a JSR.-Jump.
' Also we packed the Label into a Variable
'*************************************
VAR.§§TST=10
: §§LAB=try
:try
DBP.The number is §§TST
JNZ.§§TST<§§LAB
JNZ.§§TST|:over
PRT.Hier
DMP.
MBX.!
END.
:over
DBP.Was here with §§TST
VDC.§§TST
RET.
'*************************************
' JNZ - Example
' with Post-Increment
'*************************************
VAR.§§TST=-50
:try
DBP.Number is: §§TST
' just jump without other features
JNZ.§§TST>try
DBP.Hier
:over
DMP.
MBX.!
END.
'*************************************
' JNZ - Example
' with Post-Decrement
'*************************************
VAR.§§TST=50
:try
DBP.Number is: §§TST
' just jump without other features
JNZ.§§TST<try
DBP.Hier
:over
DMP.
MBX.!
END.
Remarks
-
Limitations:
-
See also:
• JME. - Jump on More or Equal
• JLE. - Jump on Less or Equal
• JSR. - Jump SubRoutine (Label)