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SixtyPical Syntax.md

SixtyPical Syntax

This is a test suite, written in Falderal format, for the syntax of the Sixtypical language, disgregarding execution, static analysis, etc.

Note that these example programs are intended to be syntactically correct, but not necessarily sensible programs.

-> Tests for functionality "Check syntax of SixtyPical program"

Rudimentary program.

| define main routine {
|     ld a, 0
|     add a, 1
| }
= ok

Program with comments.

| // Welcome to my program.
| 
| define main routine {
|     ld a, 0
|     add a, 1    // We are adding the thing.
|     sub a, 1
|     shl a
|     shr a
|     and a, 1
|     or a, 1
|     xor a, 1
| }
= ok

Hex literals.

| define main routine {
|     ld a, $ff
|     add a, $01
| }
= ok

Syntax error.

| define foo routine (
|     ld a, 0
|     add a, 1
| )
? SyntaxError

Another syntax error.

| byte glee
| {
|     ld a, 0
|     add a, 1
| }
? SyntaxError

Extern routines

| define chrout routine
|   inputs a
|   trashes a
|   @ 65490
| 
| define chrin routine
|   outputs a
|   trashes x
|   @ 65487
= ok

Preserved routine.

| define main routine {
|     ld a, $ff
|     add a, $01
| }
| define foo preserved routine {
|     ld a, 0
|     add a, 1
| }
= ok

Trash.

| define main routine {
|     trash a
|     trash n
| }
= ok

nop.

| define main routine
| {
|     nop
| }
= ok

If with not

| define foo routine {
|     ld y, 0
|     cmp y, 10
|     if not z {
|         inc y
|         cmp y, 10
|     }
| }
= ok

Repeat loop

| define foo routine {
|     ld y, 0
|     repeat {
|         inc y
|         cmp y, 10
|     } until z
| }
= ok

"While" loop

| define foo routine inputs y {
|     repeat {
|         cmp y, 10
|         if not z {
|             inc y
|         }
|     } until z
| }
= ok

Repeat forever

| define foo routine inputs y {
|     repeat {
|         inc y
|     } forever
| }
= ok

Repeat with not

| define foo routine inputs y {
|     repeat {
|         inc y
|     } until not z
| }
= ok

Basic "open-faced for" loops, up and down.

| byte table[256] tab
| 
| define foo routine trashes a, x, c, z, v {
|     ld x, 0
|     for x up to 15 {
|         ld a, tab + x
|     }
|     ld x, 15
|     for x down to 0 {
|         ld a, tab + x
|     }
| }
= ok

Other blocks.

| byte table[256] tab
| pointer ptr
| 
| define main routine trashes a, x, c, z, v {
|     with interrupts off {
|         save a, x, c {
|             ld a, 0
|         }
|     }
|     save a, x, c {
|         ld a, 0
|     }
|     point ptr into tab {
|         reset ptr 0
|         ld a, [ptr] + y
|     }
| }
= ok

User-defined memory addresses of different types.

| byte byt
| word wor
| vector routine trashes a vec
| byte table[2048] buf
| pointer ptr
| 
| define main routine {
| }
= ok

Tables of different types and some operations on them.

| byte table[256] many
| word table[256] wmany
| vector (routine trashes a) table[256] vmany
| byte bval
| word wval
| 
| define main routine {
|     ld x, 0
|     ld a, 0
|     st off, c
|     add a, many + x
|     sub a, many + x
|     cmp a, many + x
|     and a, many + x
|     or a, many + x
|     xor a, many + x
|     shl many + x
|     shr many + x
|     inc many + x
|     dec many + x
|     ld a, many + x
|     st a, many + x
|     copy wval, wmany + x
|     copy wmany + x, wval
| }
= ok

Indexing with an offset in some tables.

| byte table[256] many
| word table[256] wmany
| byte bval
| word wval
| 
| define main routine {
|     ld x, 0
|     ld a, 0
|     st off, c
|     add a, many + 100 + x
|     sub a, many + 100 + x
|     cmp a, many + 100 + x
|     and a, many + 100 + x
|     or a, many + 100 + x
|     xor a, many + 100 + x
|     shl many + 100 + x
|     shr many + 100 + x
|     inc many + 100 + x
|     dec many + 100 + x
|     ld a, many + 100 + x
|     st a, many + 100 + x
|     copy wval, wmany + 100 + x
|     copy wmany + 100 + x, wval
| }
= ok

The number of entries in a table must be greater than 0 and less than or equal to 65536.

(In previous versions, a table could have at most 256 entries. They can now have more, however the offset-access syntax can only access the first 256. To access more, a pointer is required.)

| word table[512] many
| 
| define main routine
|   inputs many
|   outputs many
|   trashes a, x, n, z
| {
|     ld x, 0
|     copy 9999, many + x
| }
= ok

| byte table[65536] many
| 
| define main routine
|   inputs many
|   outputs many
|   trashes a, x, n, z
| {
|     ld x, 0
|     copy 99, many + x
| }
= ok

| byte table[65537] many
| 
| define main routine
|   inputs many
|   outputs many
|   trashes a, x, n, z
| {
|     ld x, 0
|     copy 99, many + x
| }
? SyntaxError

| word table[0] many
| 
| define main routine
|   inputs many
|   outputs many
|   trashes a, x, n, z
| {
|     ld x, 0
|     copy 9999, many + x
| }
? SyntaxError

| word table[48] many
| 
| define main routine
|   inputs many
|   outputs many
|   trashes a, x, n, z
| {
|     ld x, 0
|     copy 9999, many + x
| }
= ok

Typedefs of different types.

| typedef byte octet
| typedef octet table[256] twokay
| typedef routine trashes a game_routine
| vector game_routine start_game
| 
| define main routine {
| }
= ok

Can't have two typedefs with the same name.

| typedef byte frank
| typedef word frank
| 
| define main routine {
| }
? SyntaxError

Constants.

| const lives 3
| const days lives
| const w1 1000
| const w2 word 0
| 
| typedef byte table[days] them
| 
| byte lark: lives
| 
| define main routine {
|   ld a, lives
| }
= ok

Named constants can be used as offsets.

| const lives 3
| const w1 1000
| 
| byte table[w1] those
| 
| define main routine {
|   ld y, 0
|   ld a, those + lives + y
| }
= ok

Can't have two constants with the same name.

| const w1 1000
| const w1 word 0
| 
| define main routine {
| }
? SyntaxError

Explicit memory address.

| byte screen @ 1024
| 
| define main routine {
|   ld a, 100
|   st a, screen
|   shl screen
|   shr screen
| }
= ok

Initialized memory locations.

| byte lives : 3
| 
| define main routine {
|   ld a, lives
|   st a, lives
| }
= ok

Cannot have both initial value and explicit address.

| byte screen : 3 @ 1024
| 
| define main routine {
|   ld a, lives
|   st a, lives
| }
? SyntaxError

User-defined locations of other types.

| byte table[256] screen @ 1024
| word r1
| word r2 @ 60000
| word r3 : 2000
| 
| define main routine {
| }
= ok

Initialized byte table, initialized with ASCII string.

| byte table[32] message : "WHAT DO YOU WANT TO DO NEXT?"
| 
| define main routine {
| }
= ok

Can't initialize anything but a byte table with a string.

| word message : "OUCH! WHAT DO YOU DO?"
| 
| define main routine {
| }
? SyntaxError

Initialized byte table, initialized with list of bytes.

| byte table[8] charmap : 0, 255, 129, 192, 0, 1, 2, 4
| 
| define main routine {
| }
= ok

Can't access an undeclared memory location.

| define main routine {
|     ld a, 0
|     st a, lives
| }
? SyntaxError

Can't define two memory locations with the same name.

| byte lives
| byte lives
| 
| define main routine {
|     ld a, 0
|     st a, lives
| }
? SyntaxError

Can't shadow the name of a register or a flag.

| byte a
| 
| define main routine {
| }
? SyntaxError

| byte z
| 
| define main routine {
| }
? SyntaxError

Can't call routine that hasn't been defined.

| define main routine {
|     ld x, 0
|     ld y, 1
|     call up
|     call up
| }
? SyntaxError

But you can call a routine that is yet to be defined, further on.

| define main routine {
|     ld x, 0
|     ld y, 1
|     call up
|     call up
| }
| define up routine {
|     ld a, 0
| }
= ok

Can't define two routines with the same name.

| define main routine {
|     inc x
|     inc y
| }
| define main routine {
|     ld x, 0
|     ld y, 1
| }
? SyntaxError

Declaring byte and word table memory location.

| byte table[256] tab
| 
| define main routine {
|     ld x, 0
|     ld y, 0
|     ld a, tab + x
|     st a, tab + y
| }
= ok

| word one
| word table[256] many
| 
| define main routine {
|     ld x, 0
|     copy one, many + x
|     copy word 0, many + x
|     copy many + x, one
| }
= ok

Declaring and calling a vector.

| vector routine
|   inputs a
|   outputs x
|   trashes a, x, z, n
|   cinv @ 788
| 
| define foo routine {
|     ld a, 0
| }
| define main routine {
|     with interrupts off {
|         copy foo, cinv
|     }
|     call cinv
| }
= ok

Only vectors can be decorated with constraints like that.

| byte cinv
|   inputs a
|   outputs x
|   trashes a, x, z, n
|   @ 788
| 
| define main routine {
| }
? SyntaxError

Constraints set may only contain labels.

| vector routine
|   inputs a
|   outputs 200
|   trashes a, x, z, n
|   cinv @ 788
| 
| define foo routine {
|     ld a, 0
| }
| define main routine {
|     with interrupts off {
|         copy foo, cinv
|     }
|     call cinv
| }
? SyntaxError

A vector can name itself in its inputs, outputs, and trashes.

| vector routine
|   inputs cinv, a
|   outputs cinv, x
|   trashes a, x, z, n
|   cinv @ 788
| 
| define foo routine {
|     ld a, 0
| }
| define main routine {
|     with interrupts off {
|         copy foo, cinv
|     }
|     call cinv
| }
= ok

A routine can be copied into a vector before the routine appears in the program. This is known as a "forward reference". You are only allowed to make forward references in the source of a copy instruction.

| vector routine
|   inputs cinv, a
|   outputs cinv, x
|   trashes a, x, z, n
|   cinv @ 788
| define main routine {
|     with interrupts off {
|         copy foo, cinv
|     }
|     call cinv
| }
| define foo routine {
|     ld a, 0
| }
= ok

goto.

| define foo routine {
|     ld a, 0
| }
| define main routine {
|     goto foo
| }
= ok

The label doesn't have to be defined yet at the point in the program text where it is gotod.

| define main routine {
|     goto foo
| }
| define foo routine {
|     ld a, 0
| }
= ok

Syntactically, you can goto a vector.

| vector routine foo
| 
| define main routine {
|     goto foo
| }
= ok

But you can't goto a label that never gets defined.

| define main routine {
|     goto foo
| }
? SyntaxError

goto may only be the final instruction in a block.

| define bar routine trashes x, z, n {
|     ld x, 200
| }
| 
| define main routine trashes x, z, n {
|     goto bar
|     ld x, 0
| }
? Expected '}', but found 'ld'

Tables and pointers.

| byte table[2048] buf
| pointer ptr
| pointer ptrb
| byte foo
| 
| define main routine {
|     point ptr into buf {
|         reset ptr 0
|         copy 123, [ptr] + y
|         copy [ptr] + y, foo
|         copy [ptr] + y, [ptrb] + y
|     }
| }
= ok

Routines can be defined in a new style.

| typedef routine
|   inputs x
|   outputs x
|   trashes z, n
|     routine_type
| 
| vector routine_type vec
| 
| define foo routine
|   inputs x
|   outputs x
|   trashes z, n
| {
|   inc x
| }
| 
| define main routine
|   outputs vec
|   trashes a, z, n
| {
|     copy foo, vec
| }
= ok

| typedef routine
|   inputs x
|   outputs x
|   trashes z, n
|     routine_type
| 
| vector routine_type vec
| 
| define foo routine_type
| {
|   inc x
| }
| 
| define main routine
|   outputs vec
|   trashes a, z, n
| {
|     copy foo, vec
| }
= ok

Only routines can be defined in the new style.

| define foo byte table[256]
| 
| routine main
|   trashes a, z, n
| {
|     ld a, 0
| }
? SyntaxError

Memory locations can be defined local to a routine.

| define foo routine
|   inputs x
|   outputs x
|   trashes z, n
|   static byte t : 0
|   local word w
| {
|   st x, t
|   inc t
|   ld x, t
| }
| 
| define main routine
|   trashes a, x, z, n
|   static byte t : 0
|   local word w
| {
|   ld x, t
|   call foo
| }
= ok

Local static memory locations must always be given an initial value.

| define main routine
|   inputs x
|   outputs x
|   trashes z, n
|   static byte t
| {
|   st x, t
|   inc t
|   ld x, t
| }
? SyntaxError

Local static memory locations may not be given an address.

| define main routine
|   inputs x
|   outputs x
|   trashes z, n
|   static byte t @ 1024
| {
|   st x, t
|   inc t
|   ld x, t
| }
? SyntaxError

Local dynamic memory locations may not be given an initial value.

| define main routine
|   inputs x
|   outputs x
|   trashes z, n
|   local byte t : 10
| {
|   st x, t
|   inc t
|   ld x, t
| }
? SyntaxError

Local dynamic memory locations may be given an address.

| define main routine
|   inputs x
|   outputs x
|   trashes z, n
|   local byte t @ 1024
| {
|   st x, t
|   inc t
|   ld x, t
| }
= ok

Name of a local cannot shadow an existing global or local.

| byte t
| 
| define main routine
|   inputs x
|   outputs x
|   trashes z, n
|   static byte t : 10
| {
|   st x, t
|   inc t
|   ld x, t
| }
? SyntaxError

| define main routine
|   inputs x
|   outputs x
|   trashes z, n
|   static byte t : 10
|   static byte t : 20
| {
|   st x, t
|   inc t
|   ld x, t
| }
? SyntaxError

| byte t
| 
| define main routine
|   inputs x
|   outputs x
|   trashes z, n
|   local byte t
| {
|   st x, t
|   inc t
|   ld x, t
| }
? SyntaxError

| define main routine
|   inputs x
|   outputs x
|   trashes z, n
|   local word w
|   local word w
| {
|   st x, t
|   inc t
|   ld x, t
| }
? SyntaxError

Since the names of locals are lexically local to a routine, they cannot appear in the inputs, outputs, trashes list of the routine.

| define main routine
|   inputs t
|   static byte t : 0
| {
|   inc t
| }
? SyntaxError

| define main routine
|   outputs t
|   static byte t : 0
| {
|   inc t
| }
? SyntaxError

| define main routine
|   trashes t
|   static byte t : 0
| {
|   inc t
| }
? SyntaxError

| define main routine
|   inputs t
|   local byte t
| {
|   inc t
| }
? SyntaxError

| define main routine
|   outputs t
|   local byte t
| {
|   inc t
| }
? SyntaxError

| define main routine
|   trashes t
|   local byte t
| {
|   inc t
| }
? SyntaxError