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

===== USER-DEFINED PROCEDURES RETURN VALUE (USING PARAM$()) =====

==== PURPOSE ====
 This example will demonstrate how to define procedures with one or more parameters. Parameters are a way to give informations to the procedure. Moreover, it shows one way to retrieve the returning value of the procedure. There are several. Anyway, the parameters should be considered like local variables that are feeded by the caller. The returning value should be considered as a value than could be used by the caller. The example will implement a procedure that merges three strings all togheter.  

==== SOURCE CODE ====
   
       CLS
       
       PROCEDURE joinString[a$,b$,c$ ]
           PRINT "joinString called with:"
           PRINT " a$ = ";a$
           PRINT " b$ = ";b$
           PRINT " c$ = ";c$
       END PROC[a$+b$+c$]
       
       joinString["ONE","TWO","THREE"]
   
       PRINT "joinString[ONE,TWO,THREE] = ";PARAM$(joinString)
   


==== SOURCE FILE ====
  * ''[[https://github.com/spotlessmind1975/ugbasic/tree/main/examples/procedures_param_01.bas|procedures_param_01.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 procedures_param_01.bas -o example.xex
   altirra example.xex
   
   # Windows 
   ugbc.atari.exe procedures_param_01.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 procedures_param_01.bas -o example.xex
   altirra example.xex
   
   # Windows 
   ugbc.atarixl.exe procedures_param_01.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 procedures_param_01.bas -o example.prg
   x64sc example.prg
   
   # Windows 
   ugbc.c64.exe procedures_param_01.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 procedures_param_01.bas -o example.prg
   x64sc -reu example.prg
   
   # Windows 
   ugbc.c64reu.exe procedures_param_01.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 procedures_param_01.bas -o example.prg
   yape example.prg
   
   # Windows 
   ugbc.plus4.exe procedures_param_01.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 procedures_param_01.bas -o example.prg
   xplus4 example.prg
   
   # Windows 
   ugbc.plus4.exe procedures_param_01.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 procedures_param_01.bas -o example.bin
   xroar -rompath (your rom path) example.bin
   
   # Windows 
   ugbc.d32.exe procedures_param_01.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 procedures_param_01.bas -o example.bin
   xroar -rompath (your rom path) example.bin
   
   # Windows 
   ugbc.d64.exe procedures_param_01.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 procedures_param_01.bas -o example.k7
   dcmoto
   (choose BASIC 128)
   CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
   
   # Windows 
   ugbc.pc128op.exe procedures_param_01.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 procedures_param_01.bas -o example.k7
   dcmoto
   (choose BASIC 128)
   CLEAR,&H2FFF: LOADM"CASS:",R: EXEC
   
   # Windows 
   ugbc.pc128op.exe procedures_param_01.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 procedures_param_01.bas -o example.prg
   xvic --memory 24k example.prg
   
   # Windows 
   ugbc.vic20.exe procedures_param_01.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 procedures_param_01.bas -o example.tap
   Speccy example.tap
   
   # Windows 
   ugbc.zx.exe procedures_param_01.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 procedures_param_01.bas -o example.rom
   openmsx -cart example.rom
   
   # Windows 
   ugbc.msx1.exe procedures_param_01.bas -o example.rom
   openmsx -cart example.rom
== blueMSX ==
   # Linux 
   ugbc.msx1 procedures_param_01.bas -o example.rom
   bluemsx example.rom
   
   # Windows 
   ugbc.msx1.exe procedures_param_01.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 procedures_param_01.bas -o example.rom
   openmsx -machine \"COL - ColecoVision\" -cart example.rom
   
   # Windows 
   ugbc.coleco.exe procedures_param_01.bas -o example.rom
   bluemsx -machine \"COL - ColecoVision\" example.rom
== blueMSX ==
   # Linux 
   ugbc.coleco procedures_param_01.bas -o example.rom
   bluemsx /machine \"COL - ColecoVision\" /rom1 example.rom
   
   # Windows 
   ugbc.coleco.exe procedures_param_01.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 procedures_param_01.bas -o example.rom
   bluemsx /machine \"SEGA - SC-3000\" /rom1 example.rom
   
   # Windows 
   ugbc.sc3000.exe procedures_param_01.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 procedures_param_01.bas -o example.rom
   bluemsx /machine \"SEGA - SG-1000\" /rom1 example.rom
   
   # Windows 
   ugbc.sg1000.exe procedures_param_01.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 USER-DEFINED PROCEDURES RETURN VALUE (USING PARAM$())|open an issue]] for this example on GitHub. Thank you!===== POWERED BY =====

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