Modified the BASIC interpreter to support comments using #

and sol whitespace support (eg tabs or spaces for indentation)

MEMORY_LAYOUT.md

@@ -0,0 +1,4 @@
+The root directory is from byte 24000h to 26FFFh<br/>
+The currently opened file's metadata is from 27000h to 2701Fh<br/>
+The to be outputted string is stored from 27020h to 27FFFh<br/>
+The currently opened file is from 28000h<br/>

README.md

@@ -49,6 +49,6 @@ To allow for easier debugging.
 # BASIC development
 Please refer to the [MikeOS BASIC documentation](https://mikeos.sourceforge.net/handbook-appdev-basic.html)<br/>
 docs on writing BASIC code. In order to create new<br/>
-files, place them in the /data/ directory, not the file<br/>
+files, place them in the /data/ directory, note the file<br/>
 names are limited to 11 characters due to FAT12 limitations<br/>
 (8 for the name and 3 for the extension).

data/fb.bas

@@ -1,5 +1,7 @@
-FOR A = 1 TO 100
-PRINT A ;
+# A cool fizzbuzz program
+PRINT "FizzBuzz!"
+FOR A = 1 TO 16
+	PRINT A ; # Prints the number
 	B = A % 3
 	C = A % 5
 	IF B = 0 then PRINT "Fizz" ;

source/kernel/features/basic.asm

@@ -3970,6 +3970,14 @@ get_token:
 	mov word si, [prog]
 	lodsb
 
+	cmp al, 09h
+	je .whitespace
+	cmp al, 20h
+	je .whitespace
+
+	cmp al, '#'
+	je .comment
+
 	cmp al, 10
 	je .newline
 
@@ -3990,13 +3998,28 @@ get_token:
 
 	jmp get_string_token
 
+.whitespace:
+	inc word [prog]
+	jmp get_token
+
+.comment:
+	inc word [prog]			; Move past first quote (") char
+	mov word si, [prog]
+	mov di, token
+	.loop:
+		lodsb
+		cmp al, 0Ah
+		je .done
+		inc word [prog]
+		jmp .loop
+	.done:
+		inc word [prog]			; Move past final quote
+		jmp get_token
 
 .newline:
 	inc word [prog]
 	jmp get_token
 
-
-
 get_number_token:
 	mov word si, [prog]
 	mov di, token
@@ -4273,6 +4296,8 @@ vars_loc:
 	work_page		db 0		; Page to print to
 	disp_page		db 0		; Page to display
 
+	tab_skip		db "	", 0
+	space_skip		db " ", 0
 	alert_cmd		db "ALERT", 0
 	askfile_cmd		db "ASKFILE", 0
 	break_cmd		db "BREAK", 0