{{htmlmetatags>metatag-robots=()
metatag-title=(OTHER CONTRIBUTIONS FOR...NEXT BEST PRACTICE | ugBASIC User Manual)
metatag-keywords=(ugBASIC,Commodore 64,Commodore PLUS/4,ZX Spectrum)
metatag-description=(An isomorphic language for retrocomputers)
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metatag-og:title=(OTHER CONTRIBUTIONS FOR...NEXT BEST PRACTICE | ugBASIC User Manual) 
metatag-og:description=(An isomorphic language for retrocomputers)
}}

====== ugBASIC User Manual ======

===== OTHER CONTRIBUTIONS FOR...NEXT BEST PRACTICE =====

==== PURPOSE ====
 This program will try to answer to the Gary Luckenbaugh's article about FOR...NEXT best practice under ugBASIC.   

==== SOURCE CODE ====
   
   CLS
   
   ''' RULE #1
   ' Always enter a FOR-NEXT loop at the FOR. Don’t even think about entering 
   ' the middle of a loop. Not surprisingly, “there be dragons here” if you 
   ' do.
   '
   ' In ugBASIC you can enter into a FOR...NEXT without problems.
   
   PRINT "RULE#1"
   PRINT
   
   DIM x1 AS BYTE
   
   x1 = 1
   
   GOTO inTheMiddle1
   
   FOR x1 = 1 TO 10
   
   inTheMiddle1:
   
   	PRINT x1;" ";
   NEXT x1
   
   PRINT
   
   ''' RULE #2
   ' Never leave a FOR-NEXT mid-flight. Use FOR-NEXT to count from the 
   ' beginning to the TO value with steps of STEP. If you feel you must 
   ' leave a FOR in mid-flight, then FOR is not the proper construct.
   '
   ' In ugBASIC you can exit out from a FOR...NEXT without problems.
   
   PRINT:PRINT "RULE #2"
   PRINT
   
   DIM x2 AS BYTE
   
   FOR x2 = 1 TO 10
   
   	PRINT x2;" ";
   	
   	IF x2 > 4 THEN GOTO outOfFor2
   	
   NEXT x2
   
   outOfFor2:
   
   PRINT
   
   ''' RULE #3
   ' If you absolutely must jump out of a FOR, then you must always 
   ' come back to where you left off. The best way to do this is 
   ' via GOSUB to jump out and then RETURN to where you were. 
   ' At the location where you jump out, there should be no 
   ' FORs with the same control variable, in this case i.
   '
   ' In ugBASIC you can jump out using GOTO (see rules #1 and #2)
   ' and you can use the same variable if you jump inside a GOSUB.
   
   ''' RULE #4
   ' Never enter a FOR loop recursively, unless you are using a modern 
   ' BASIC, and even then use recursive subs/functions and not GOTOs 
   ' or GOSUBS
   '
   ' ugBASIC does not support recursion
   
   ''' RULE #5
   ' Don’t try to change the final value or the step when a FOR-NEXT 
   ' is in-flight. You may get away with this on some BASICs and 
   ' not on others.
   '
   ' In ugBASIC you can change initial, final and step value.
   
   PRINT:PRINT "RULE #5"
   PRINT
   
   DIM x5 AS BYTE, f5 AS BYTE, t5 AS BYTE, s5 AS BYTE
   
   f5 = 1: t5 = 10: s5 = 2
   
   FOR x5 = f5 TO t5 STEP s5
   
   	PRINT x5; " ";
   	
   	IF x5 > 4 THEN
   		t5 = 10
   		s5 = 4
   	ENDIF
   	
   NEXT 
   
   PRINT
   
   ''' RULE #6
   ' Don’t change the control variable in-flight:
   '
   ' In ugBASIC you can change the contro variable, as you like.
   
   PRINT:PRINT "RULE #6"
   PRINT
   
   DIM x6 AS BYTE
   
   FOR x6 = 1 TO 10
   
   	PRINT x6;" ";
   	
   	IF x6 > 3 THEN x6 = 10
   		
   NEXT 
   
   PRINT
   
   ''' RULE #7
   ' Draw a line from each FOR to the corresponding NEXT, and make 
   ' sure no lines overlap, as depicted below:
   '
   '     +-- for i = 1 to 10
   '     |
   '+----|--------for j = 1 to 10
   '+    |
   '+    +---next i
   '+
   '+-------next j
   '
   ' Also ugBASIC respects this rule.
   
   


==== SOURCE FILE ====
  * ''[[https://github.com/spotlessmind1975/ugbasic/tree/main/examples/contrib_for_next_bp.bas|contrib_for_next_bp.bas]]''
==== HOW TO COMPILE AND RUN ====
The instructions here refer to compiling the example from the command line. For Microsoft Windows users we suggest using **[[https://spotlessmind1975.itch.io/ugbasic-ide|UGBASIC-IDE]]**, which allows you to compile the example with just one click.=== ATARI 400/800 family ===
In order to compile and run the example, you need to have the Altirra emulator, and in particular that the ''altirra'' executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.atari contrib_for_next_bp.bas -o example.xex
   altirra example.xex
   
   # Windows 
   ugbc.atari.exe contrib_for_next_bp.bas -o example.xex
   altirra example.xex
=== ATARI 600XL/800XL/1200XL/XG(SE) family ===
In order to compile and run the example, you need to have the Altirra emulator, and in particular that the ''altirra'' executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.atarixl contrib_for_next_bp.bas -o example.xex
   altirra example.xex
   
   # Windows 
   ugbc.atarixl.exe contrib_for_next_bp.bas -o example.xex
   altirra example.xex
=== Commodore 64 ===
In order to compile and run the example, you need to have the VICE emulator, and in particular that the ''x64sc'' executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.c64 contrib_for_next_bp.bas -o example.prg
   x64sc example.prg
   
   # Windows 
   ugbc.c64.exe contrib_for_next_bp.bas -o example.prg
   x64sc example.prg
=== Commodore 64+REU ===
In order to compile and run the example, you need to have the VICE emulator, and in particular that the ''x64sc'' executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.c64reu contrib_for_next_bp.bas -o example.prg
   x64sc -reu example.prg
   
   # Windows 
   ugbc.c64reu.exe contrib_for_next_bp.bas -o example.prg
   x64sc -reu example.prg
=== Commodore PLUS/4 ===
== Using YAPE ==
In order to run the example, you need to have the YAPE emulator. In particular that the ''yape'' executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.plus4 contrib_for_next_bp.bas -o example.prg
   yape example.prg
   
   # Windows 
   ugbc.plus4.exe contrib_for_next_bp.bas -o example.prg
   yape example.prg
== Using VICE ==
In order to run the example, you need to have the VICE emulator. In particular that the ''xplus4'' executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.plus4 contrib_for_next_bp.bas -o example.prg
   xplus4 example.prg
   
   # Windows 
   ugbc.plus4.exe contrib_for_next_bp.bas -o example.prg
   xplus4 example.prg
=== Dragon 32 ===
In order to compile and run the example, you need to have the XROAR emulator, and in particular that the ''xroar'' executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.d32 contrib_for_next_bp.bas -o example.bin
   xroar -rompath (your rom path) example.bin
   
   # Windows 
   ugbc.d32.exe contrib_for_next_bp.bas -o example.bin
   xroar.exe -rompath (your rom path) example.bin
=== Dragon 64 ===
In order to compile and run the example, you need to have the XROAR emulator, and in particular that the ''xroar'' executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.d64 contrib_for_next_bp.bas -o example.bin
   xroar -rompath (your rom path) example.bin
   
   # Windows 
   ugbc.d64.exe contrib_for_next_bp.bas -o example.bin
   xroar.exe -rompath (your rom path) example.bin
=== PC128 Olivetti Prodest ===
In order to compile and run the example, you need to have the DCMOTO emulator, and in particular that the ''dcmoto'' executable is accessible.

Then, type this command on the command line and on the emulator:

   # Linux 
   ugbc.pc128op contrib_for_next_bp.bas -o example.k7
   dcmoto
   (choose BASIC 128)
   CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
   
   # Windows 
   ugbc.pc128op.exe contrib_for_next_bp.bas -o example.k7
   dcmoto
   (choose example.k7)
   (choose BASIC 128)
   CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
=== Thomson MO5 ===
In order to compile and run the example, you need to have the DCMOTO emulator, and in particular that the ''dcmoto'' executable is accessible.

Then, type this command on the command line and on the emulator:

   # Linux 
   ugbc.pc128op contrib_for_next_bp.bas -o example.k7
   dcmoto
   (choose BASIC 128)
   CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
   
   # Windows 
   ugbc.pc128op.exe contrib_for_next_bp.bas -o example.k7
   dcmoto
   (choose example.k7)
   (choose BASIC 128)
   CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
=== Commodore VIC-20 ===
In order to compile and run the example, you need to have the VICE emulator, and in particular that the ''xvic'' executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.vic20 contrib_for_next_bp.bas -o example.prg
   xvic --memory 24k example.prg
   
   # Windows 
   ugbc.vic20.exe contrib_for_next_bp.bas -o example.prg
   xvic --memory 24k example.prg
=== ZX Spectrum ===
In order to compile and run the example, you need to have the Speccy emulator, and in particular that the ''speccy'' executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.zx contrib_for_next_bp.bas -o example.tap
   Speccy example.tap
   
   # Windows 
   ugbc.zx.exe contrib_for_next_bp.bas -o example.tap
   Speccy example.tap
=== MSX ===
In order to compile and run the example, you need to have the openMsx or the BlueMSX emulator, and in particular that its executable is accessible.

Then, type this command on the command line:

== openMSX ==
   # Linux 
   ugbc.msx1 contrib_for_next_bp.bas -o example.rom
   openmsx -cart example.rom
   
   # Windows 
   ugbc.msx1.exe contrib_for_next_bp.bas -o example.rom
   openmsx -cart example.rom
== blueMSX ==
   # Linux 
   ugbc.msx1 contrib_for_next_bp.bas -o example.rom
   bluemsx example.rom
   
   # Windows 
   ugbc.msx1.exe contrib_for_next_bp.bas -o example.rom
   bluemsx example.rom
=== ColecoVision ===
In order to compile and run the example, you need to have the openMsx or the BlueMSX emulator, and in particular that its executable is accessible.

Then, type this command on the command line:

== openMSX ==
   # Linux 
   ugbc.coleco contrib_for_next_bp.bas -o example.rom
   openmsx -machine \"COL - ColecoVision\" -cart example.rom
   
   # Windows 
   ugbc.coleco.exe contrib_for_next_bp.bas -o example.rom
   bluemsx -machine \"COL - ColecoVision\" example.rom
== blueMSX ==
   # Linux 
   ugbc.coleco contrib_for_next_bp.bas -o example.rom
   bluemsx /machine \"COL - ColecoVision\" /rom1 example.rom
   
   # Windows 
   ugbc.coleco.exe contrib_for_next_bp.bas -o example.rom
   bluemsx  /machine \"COL - ColecoVision\" /rom1 example.rom
=== SEGA SC-3000 ===
In order to compile and run the example, you need to have the BlueMSX emulator, and in particular that its executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.sc3000 contrib_for_next_bp.bas -o example.rom
   bluemsx /machine \"SEGA - SC-3000\" /rom1 example.rom
   
   # Windows 
   ugbc.sc3000.exe contrib_for_next_bp.bas -o example.rom
   bluemsx  /machine \"SEGA - SC-3000\" /rom1 example.rom
=== SEGA SG-1000 ===
In order to compile and run the example, you need to have the BlueMSX emulator, and in particular that its executable is accessible.

Then, type this command on the command line:

   # Linux 
   ugbc.sg1000 contrib_for_next_bp.bas -o example.rom
   bluemsx /machine \"SEGA - SG-1000\" /rom1 example.rom
   
   # Windows 
   ugbc.sg1000.exe contrib_for_next_bp.bas -o example.rom
   bluemsx  /machine \"SEGA - SG-1000\" /rom1 example.rom
==== ANY PROBLEM? ====
If you have found a problem trying to run this example, if you think there is a bug or, more simply, you would like it to be improved, [[https://github.com/spotlessmind1975/ugbasic/issues/new?title=IMPROVE OTHER CONTRIBUTIONS FOR...NEXT BEST PRACTICE|open an issue]] for this example on GitHub. Thank you!===== POWERED BY =====

[[:ugbasic:user:examples|{{ :ugbasic:user:logo-ugbasic.png?nolink&600 |}}]]