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Change comment symbol to '//'

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David Schmenk 2014-08-15 21:22:09 -07:00
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commit 4bafac2513
1 changed files with 25 additions and 25 deletions
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README.md
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@ -98,16 +98,16 @@ The PLASMA low level operations are defined as:
Although the low-level operations could easily by coded by hand, they were chosen to be an easy target for a simple compiler. Think along the lines of an advanced assembler or stripped down C compiler ( C--). Taking concepts from BASIC, Pascal, C and assembler, the PLASMA compiler is simple yet expressive. The syntax is line oriented; there is no statement delimiter except newline. Although the low-level operations could easily by coded by hand, they were chosen to be an easy target for a simple compiler. Think along the lines of an advanced assembler or stripped down C compiler ( C--). Taking concepts from BASIC, Pascal, C and assembler, the PLASMA compiler is simple yet expressive. The syntax is line oriented; there is no statement delimiter except newline.
Comments are allowed throughout the source, starting with the ‘;’ character. The rest of the line is ignored. Comments are allowed throughout the source, starting with the ‘//’ symbol. The rest of the line is ignored.
``` ```
; Data and text buffer constants // Data and text buffer constants
``` ```
Hexadecimal constants are preceded with a ‘$’ to identify them as such. Hexadecimal constants are preceded with a ‘$’ to identify them as such.
``` ```
$C030 ; Speaker address $C030 // Speaker address
``` ```
### Constants, Variables and Functions ### Constants, Variables and Functions
@ -115,27 +115,27 @@ Hexadecimal constants are preceded with a ‘$’ to identify them as such.
The source code of a PLASMA module first defines imports, constants, variables and data. Constants must be initialized with a value. Variables can have sizes associated with them to declare storage space. Data can be declared with or without a variable name associated with it. Arrays, tables, strings and any predeclared data can be created and accessed in multiple ways. The source code of a PLASMA module first defines imports, constants, variables and data. Constants must be initialized with a value. Variables can have sizes associated with them to declare storage space. Data can be declared with or without a variable name associated with it. Arrays, tables, strings and any predeclared data can be created and accessed in multiple ways.
``` ```
; //
; Import standard library functions. // Import standard library functions.
; //
import stdlib import stdlib
predef putc, puts, getc, gets, cls, memcpy, memset, memclr predef putc, puts, getc, gets, cls, memcpy, memset, memclr
end end
; //
; Constants used for hardware and flags // Constants used for hardware and flags
; //
const speaker = $C030 const speaker = $C030
const changed = 1 const changed = 1
const insmode = 2 const insmode = 2
; //
; Array declaration of screen row addresses // Array declaration of screen row addresses
; //
word txtscrn[] = $0400,$0480,$0500,$0580,$0600,$0680,$0700,$0780 word txtscrn[] = $0400,$0480,$0500,$0580,$0600,$0680,$0700,$0780
word = $0428,$04A8,$0528,$05A8,$0628,$06A8,$0728,$07A8 word = $0428,$04A8,$0528,$05A8,$0628,$06A8,$0728,$07A8
word = $0450,$04D0,$0550,$05D0,$0650,$06D0,$0750,$07D0 word = $0450,$04D0,$0550,$05D0,$0650,$06D0,$0750,$07D0
; //
; Misc global variables // Misc global variables
; //
byte flags = 0 byte flags = 0
word numlines = 0 word numlines = 0
byte cursx, cursy byte cursx, cursy
@ -147,9 +147,9 @@ Variables can have optional brackets; empty brackets don’t reserve any space f
Strings are defined like Pascal strings, a length byte followed by the string characters so they can be a maximum of 255 characters long. Strings can only appear in the variable definitions of a module. String constants can’t be used in expressions or statements. Strings are defined like Pascal strings, a length byte followed by the string characters so they can be a maximum of 255 characters long. Strings can only appear in the variable definitions of a module. String constants can’t be used in expressions or statements.
``` ```
; //
; An initialized string of 64 characters // An initialized string of 64 characters
; //
byte txtfile[64] = "UNTITLED" byte txtfile[64] = "UNTITLED"
``` ```
@ -199,7 +199,7 @@ Functions with parameters or expressions to be used as a function address to cal
word keyin word keyin
byte key byte key
keyin = @keyin2plus ; address-of keyin2plus function keyin = @keyin2plus // address-of keyin2plus function
key = keyin() key = keyin()
``` ```
@ -210,7 +210,7 @@ Expressions are algebraic. Data is free-form, but all operations on the evaluat
``` ```
const speaker=$C030 const speaker=$C030
^speaker ; click speaker ^speaker // click speaker
close(refnum) close(refnum)
``` ```
@ -261,11 +261,11 @@ Control structures affect the flow of control through the program. There are co
``` ```
if ^pushbttn3 < 128 if ^pushbttn3 < 128
if key == $C0 if key == $C0
key = $D0 ; P key = $D0 // P
elsif key == $DD elsif key == $DD
key = $CD ; M key = $CD // M
elsif key == $DE elsif key == $DE
key = $CE ; N key = $CE // N
fin fin
else else
key = key | $E0 key = key | $E0
@ -350,7 +350,7 @@ call(aReg, xReg, yReg, statusReg, addr) returns a pointer to a four byte structu
const xreg = 1 const xreg = 1
const getlin = $FD6A const getlin = $FD6A
numchars = (call(0, 0, 0, 0, getlin)).xreg ; return char count in X reg numchars = (call(0, 0, 0, 0, getlin)).xreg // return char count in X reg
``` ```
syscall(cmd, params) calls ProDOS, returning the status value. syscall(cmd, params) calls ProDOS, returning the status value.
@ -380,7 +380,7 @@ memset(addr, len, val) will fill memory with a 16 bit value. memcpy(dstaddr, sr
``` ```
byte nullstr[] = "" byte nullstr[] = ""
memset(strlinbuf, maxfill * 2, @nullstr) ; fill line buff with pointer to null string memset(strlinbuf, maxfill * 2, @nullstr) // fill line buff with pointer to null string
memcpy(scrnptr, strptr + ofst + 1, numchars) memcpy(scrnptr, strptr + ofst + 1, numchars)
``` ```