TOKENS {

# First token must be "END"

TOK_END

# Constant and variable loading

TOK_NUM, TOK_BYTE, TOK_CSTRING, TOK_VAR_ADDR, TOK_VAR_SADDR, TOK_VAR_LOAD

TOK_SHL8, TOK_0, TOK_1

# PUSH plus composed PUSH ops

TOK_PUSH, TOK_PUSH_VAR_LOAD

TOK_PUSH_NUM, TOK_PUSH_BYTE, TOK_PUSH_0, TOK_PUSH_1, TOK_POP

# Numeric operators

TOK_NEG, TOK_ABS, TOK_SGN, TOK_ADD, TOK_SUB, TOK_MUL, TOK_DIV, TOK_MOD

# Operators on VAR

TOK_ADD_VAR,

# Bitwise operators

TOK_BIT_AND, TOK_BIT_OR, TOK_BIT_EXOR

# Functions

TOK_PEEK, TOK_DPEEK, TOK_BYTE_PEEK

TOK_TIME, TOK_RAND

# Boolean operators

TOK_L_NOT, TOK_L_OR, TOK_L_AND

# Comparisons

TOK_LT, TOK_GT, TOK_NEQ, TOK_EQ

# Convert from int to bool

TOK_COMP_0

# Low level statements

TOK_POKE, TOK_DPOKE, TOK_MOVE, TOK_NMOVE, TOK_MSET, TOK_INC, TOK_DEC

TOK_VAR_STORE, TOK_SADDR, TOK_INCVAR, TOK_DECVAR, TOK_BYTE_POKE

TOK_NUM_POKE, TOK_VAR_STORE_0

# Position (used also in graphics)

TOK_POSITION

# Print statements

TOK_PRINT_STR, TOK_PRINT_TAB, TOK_PRINT_RTAB

# Simple console input and output

TOK_GETKEY, TOK_INPUT_STR, TOK_PUT, TOK_BYTE_PUT

# Jumps

TOK_JUMP, TOK_CJUMP, TOK_CNJUMP, TOK_CALL, TOK_RET, TOK_CRET, TOK_CNRET

# FOR loop support

TOK_FOR, TOK_FOR_NEXT, TOK_FOR_EXIT

# Arrays

TOK_DIM, TOK_USHL

# Strings

TOK_COPY_STR, TOK_VAL, TOK_CMP_STR, TOK_INT_STR, TOK_STR_IDX, TOK_CAT_STR, TOK_CHR

TOK_PAUSE

# USR, calls ML routine

TOK_USR_ADDR, TOK_USR_PARAM, TOK_USR_CALL

}

EXTERN {

E_REM, E_NUMBER_WORD, E_NUMBER_BYTE, E_EOL

E_PUSH_LT, E_POP_LOOP, E_POP_REPEAT

E_POP_IF, E_ELSEIF, E_EXIT_LOOP

E_POP_WHILE, E_POP_FOR, E_POP_PROC_DATA, E_POP_PROC_2

E_CONST_STRING

E_VAR_CREATE, E_VAR_SET_TYPE, E_LABEL_SET_TYPE

E_VAR_WORD, E_VAR_SEARCH

E_LABEL, E_LABEL_DEF, E_LABEL_CREATE, E_DO_EXEC

E_PUSH_VAR, E_POP_VAR

}

SYMBOLS {

LT_DO_LOOP = importzp

LT_ELIF = importzp

LT_ELSE = importzp

LT_FOR_1 = importzp

LT_FOR_2 = importzp

LT_IF = importzp

LT_PROC_2 = importzp

LT_REPEAT = importzp

LT_WHILE_1 = importzp

LT_WHILE_2 = importzp

VT_ARRAY_BYTE = importzp

VT_ARRAY_STRING = importzp

VT_ARRAY_WORD = importzp

VT_STRING = importzp

VT_WORD = importzp

BASIC_TOP = importzp

IOERROR = importzp

PRINT_COLOR = importzp

PRINT_RTAB_ARG = importzp

MEMTOP = import

CLEAR_DATA = import

ATEOL = 155

ATCLS = $7D

}

INT_EXPR: integer expression

T_EXPR BIT_EXPR_MORE M_EXPR_MORE INT_EXPR_MORE

PUSH_T_EXPR: integer expression

# Those produce about 1% faster code in the IDE for 12 extra bytes.

emit TOK_PUSH T_EXPR

INT_EXPR_MORE:

"+" PUSH_T_EXPR BIT_EXPR_MORE M_EXPR_MORE emit TOK_ADD INT_EXPR_MORE

"-" PUSH_T_EXPR BIT_EXPR_MORE M_EXPR_MORE emit TOK_SUB INT_EXPR_MORE

pass

M_EXPR_MORE:

"*" PUSH_T_EXPR BIT_EXPR_MORE emit TOK_MUL M_EXPR_MORE

"/" PUSH_T_EXPR BIT_EXPR_MORE emit TOK_DIV M_EXPR_MORE

"Mod" PUSH_T_EXPR BIT_EXPR_MORE emit TOK_MOD M_EXPR_MORE

pass

BIT_EXPR_MORE:

"&" PUSH_T_EXPR emit TOK_BIT_AND BIT_EXPR_MORE

"!" PUSH_T_EXPR emit TOK_BIT_OR BIT_EXPR_MORE

"Exor" PUSH_T_EXPR emit TOK_BIT_EXOR BIT_EXPR_MORE

pass

ADR_EXPR: string or variable

STR_EXPR

emit { TOK_VAR_LOAD, VT_ARRAY_WORD } E_VAR_SEARCH

emit { TOK_VAR_LOAD, VT_ARRAY_BYTE } E_VAR_SEARCH

emit { TOK_NUM, VT_ARRAY_WORD } E_LABEL

emit { TOK_NUM, VT_ARRAY_BYTE } E_LABEL

emit { TOK_VAR_LOAD, VT_ARRAY_STRING } E_VAR_SEARCH

emit { TOK_VAR_ADDR } E_VAR_WORD

USR_EXPR_MORE:

"," EXPR emit TOK_USR_PARAM USR_EXPR_MORE

pass

T_EXPR: integer constant, variable or function

emit TOK_BYTE E_NUMBER_BYTE

emit TOK_NUM E_NUMBER_WORD

"-" T_EXPR emit TOK_NEG

"+" T_EXPR

PAR_EXPR

INT_FUNCTIONS

INT_FUNCTIONS: integer variable or function

"Not" NOT_EXPR emit TOK_L_NOT

# Special (predefined) variables

"Time" emit TOK_TIME

# Variables as R-Values, push value into stack

ARRAY_WORD_ADDR emit TOK_DPEEK

ARRAY_BYTE_ADDR emit TOK_PEEK

# Functions without parameters

"Fre()" emit { TOK_NUM, &MEMTOP, TOK_DPEEK, TOK_PUSH_BYTE, BASIC_TOP, TOK_DPEEK, TOK_SUB }

"Err()" emit { TOK_BYTE_PEEK, IOERROR }

"Key()" emit { TOK_NUM, &CH, TOK_PEEK, TOK_PUSH_BYTE, 255, TOK_BIT_EXOR }

# Variables

emit TOK_VAR_LOAD E_VAR_WORD

# Functions with parameters

"Abs" T_EXPR emit TOK_ABS

"SGn" T_EXPR emit TOK_SGN

"Peek" T_EXPR emit TOK_PEEK

"PAddle" emit { TOK_NUM, &PADDL0, TOK_PUSH_BYTE, 7 } RD_PORT

"PTrig" emit { TOK_NUM, &PTRIG0, TOK_PUSH_BYTE, 7 } RD_PORT

"Stick" emit { TOK_NUM, &STICK0, TOK_PUSH_BYTE, 3 } RD_PORT

"STRig" emit { TOK_NUM, &STRIG0, TOK_PUSH_BYTE, 3 } RD_PORT

"Rand" T_EXPR emit TOK_RAND

"Dpeek" T_EXPR emit TOK_DPEEK

"USR(" EXPR emit TOK_USR_ADDR USR_EXPR_MORE ")" emit TOK_USR_CALL

"ADR(" ADR_EXPR ")"

"&" ADR_EXPR

"Len" STR_EXPR emit TOK_PEEK # First byte of string is the length

"Val" STR_EXPR emit TOK_VAL

"ASc" STR_EXPR emit { TOK_PUSH_1, TOK_ADD, TOK_PEEK } # TODO: does not check for empty strings.

RD_PORT:

emit TOK_PUSH T_EXPR emit { TOK_BIT_AND, TOK_ADD, TOK_PEEK }

PAR_EXPR: left parenthesis

"(" EXPR ")"

OR_AND_BOOL:

OR_EXPR_RIGHT

AND_EXPR_RIGHT OR_EXPR_MORE

TEST_BOOL_EXPR:

emit TOK_COMP_0 OR_AND_BOOL

emit TOK_PUSH COMP_EXPR_RIGHT AND_EXPR_MORE OR_EXPR_MORE COMP_EXPR_MORE

pass

EXPR:

INT_EXPR TEST_BOOL_EXPR

STR_EXPR COMP_STR_RIGHT

FORCE_BOOL_EXPR:

NOT_EXPR AND_EXPR_MORE OR_EXPR_MORE

OR_EXPR_RIGHT: 'OR'

"Or" emit TOK_PUSH NOT_EXPR AND_EXPR_MORE emit TOK_L_OR OR_EXPR_MORE

OR_EXPR_MORE:

OR_EXPR_RIGHT

pass

AND_EXPR_RIGHT: 'AND'

"And" emit TOK_PUSH NOT_EXPR emit TOK_L_AND AND_EXPR_MORE

AND_EXPR_MORE:

AND_EXPR_RIGHT

pass

NOT_EXPR:

"Not" NOT_EXPR emit TOK_L_NOT

INT_EXPR COMP_OR_BOOL

STR_EXPR COMP_STR_RIGHT

COMP_OR_BOOL:

emit TOK_PUSH COMP_EXPR_RIGHT COMP_EXPR_MORE

emit TOK_COMP_0

COMP_EXPR_RIGHT: integer comparison operator

"<=" INT_EXPR emit { TOK_GT, TOK_L_NOT }

">=" INT_EXPR emit { TOK_LT, TOK_L_NOT }

"<>" INT_EXPR emit TOK_NEQ

"<" INT_EXPR emit TOK_LT

">" INT_EXPR emit TOK_GT

"=" INT_EXPR emit TOK_EQ

PCMP_STR_EXPR:

emit TOK_PUSH STR_EXPR emit TOK_CMP_STR

COMP_STR_RIGHT: comparison operator

"=" PCMP_STR_EXPR emit TOK_EQ

">" PCMP_STR_EXPR emit TOK_GT

">=" PCMP_STR_EXPR emit { TOK_LT, TOK_L_NOT }

"<>" PCMP_STR_EXPR emit TOK_NEQ

"<=" PCMP_STR_EXPR emit { TOK_GT, TOK_L_NOT }

"<" PCMP_STR_EXPR emit TOK_LT

COMP_EXPR_MORE:

emit TOK_PUSH COMP_EXPR_RIGHT COMP_EXPR_MORE

pass

STR_EXPR: string expression

"(" STR_EXPR ")"

STRING_FUNCTIONS OPT_STR_INDEX

OPT_STR_INDEX:

"[" emit TOK_PUSH EXPR C_EXPR "]" emit TOK_STR_IDX OPT_STR_INDEX

"[" emit TOK_PUSH EXPR "]" emit { TOK_PUSH_BYTE, 255, TOK_STR_IDX } OPT_STR_INDEX

pass

STRING_FUNCTIONS:

# Either, a constant string

"\"" emit TOK_CSTRING E_CONST_STRING

# Or a string function

"CHR$" T_EXPR emit TOK_CHR

"STR$" T_EXPR emit TOK_INT_STR

# Convert pointer to string!

"$" PAR_EXPR

# Or a string array

ARRAY_STRING_ADDR emit TOK_DPEEK

PRINT_SEP:

"Tab" T_EXPR emit TOK_PRINT_TAB

# Right-TAB and COLOR are complicated because we need to apply it to the *next*

# parameter, so we read that parameter and the next optional separator:

"RTab" T_EXPR emit { TOK_BYTE_POKE, PRINT_RTAB_ARG } PRINT_ONE emit { TOK_PRINT_RTAB } PRINT_EOL

"Color" T_EXPR emit { TOK_BYTE_POKE, PRINT_COLOR } PRINT_NO_EOL emit { TOK_0, TOK_BYTE_POKE, PRINT_COLOR }

"," emit { TOK_BYTE, 10, TOK_PRINT_TAB }

";"

PRINT_ONE:

EXPR emit { TOK_INT_STR }

STR_EXPR

PRINT_NO_EOL:

E_EOL

PRINT_SEP PRINT_NO_EOL

PRINT_ONE emit TOK_PRINT_STR PRINT_EOL

PRINT_EOL:

E_EOL emit { TOK_BYTE_PUT, ATEOL }

PRINT_NO_EOL

THEN_OR_MULTILINE: 'THEN'

"Then" PARSE_START E_POP_IF

pass

VAR_CREATE_TYPE:

"$" emit VT_STRING

ARRAY_STRING_ADDR emit TOK_SADDR

VAR_WORD_SAVE: variable name

E_VAR_CREATE VAR_CREATE_TYPE E_VAR_SET_TYPE

E_VAR_WORD E_PUSH_VAR

EQUAL: '='

"="

STEP_OPTIONAL: 'STEP'

"Step" emit TOK_PUSH EXPR

emit TOK_PUSH_1

NEXT_VARNAME:

E_VAR_WORD

emit 0

POSITION:

EXPR C_EXPR emit TOK_POSITION

ARRAY_WORD_ADDR:

emit { TOK_VAR_LOAD, VT_ARRAY_WORD } E_VAR_SEARCH emit TOK_PUSH PAR_EXPR emit { TOK_USHL, TOK_ADD }

emit { TOK_NUM, VT_ARRAY_WORD } E_LABEL emit TOK_PUSH PAR_EXPR emit { TOK_USHL, TOK_ADD }

ARRAY_STRING_ADDR:

emit { TOK_VAR_LOAD, VT_ARRAY_STRING } E_VAR_SEARCH "$" emit TOK_PUSH PAR_EXPR emit { TOK_USHL, TOK_ADD }

"," DIM_VAR DIM_MORE

"\"" emit TOK_CSTRING E_CONST_STRING emit TOK_PRINT_STR PRINT_SEP # Prints a given string

";" # If starts with ';' don't print anyting

emit { TOK_BYTE_PUT, 63 } # Prints a '?' by default

INPUT_VAR_LIST:

INPUT_VAR INPUT_VAR_MORE

INPUT_VAR_MORE:

"," INPUT_VAR_LIST

pass

INPUT_VAR:

VAR_WORD_LVALUE_SADDR emit { TOK_INPUT_STR, TOK_VAL, TOK_DPOKE }

ARRAY_BYTE_ADDR emit { TOK_SADDR, TOK_INPUT_STR, TOK_VAL, TOK_POKE }

VAR_STR_LVALUE_SADDR emit { TOK_INPUT_STR, TOK_COPY_STR }

TYPE_WORD:

"Word" emit VT_ARRAY_WORD

emit VT_ARRAY_WORD

TYPE_BYTE:

"Byte" emit VT_ARRAY_BYTE

DIM_VAR_TYPE:

"$" PAR_EXPR emit { TOK_PUSH_1, TOK_ADD, TOK_USHL, VT_ARRAY_STRING }

emit { VT_STRING } E_VAR_SEARCH "$" E_PUSH_VAR

IO_CHAN_OPT:

pass

IO_CHAN_OPT_NOCOMMA:

pass

IO_CHAN0:

GETK_EXPR:

ARRAY_BYTE_ADDR emit { TOK_SADDR, TOK_GETKEY, TOK_POKE }

VAR_WORD_LVALUE_SADDR emit { TOK_GETKEY, TOK_DPOKE }

C_EXPR: comma followed by an expression

"," emit TOK_PUSH EXPR

EXPR_AB:

"," EXPR emit { TOK_USHL, TOK_USHL, TOK_USHL, TOK_USHL } C_EXPR emit TOK_ADD

DATA_WORDS: data word

"," E_NUMBER_WORD DATA_WORDS

pass

DATA_BYTE:

"\"" E_CONST_STRING

E_NUMBER_BYTE

emit { VT_ARRAY_BYTE } E_LABEL

DATA_BYTES: data byte

# To store bytes, simply remove upper part

DATA_BYTE "," DATA_BYTES

DATA_BYTE

DATA_EXT_TYPE: extended data type

pass

DATA_TYPE: data type

TYPE_BYTE DATA_EXT_TYPE EQUAL E_LABEL_SET_TYPE DATA_BYTES

TYPE_WORD DATA_EXT_TYPE EQUAL E_LABEL_SET_TYPE E_NUMBER_WORD DATA_WORDS

DATA_END:

","

E_POP_PROC_DATA

DATA_VAR: new data array name

DATA_TYPE

E_LABEL_CREATE "()" emit { TOK_JUMP } E_LABEL_DEF DATA_TYPE

PAUSE_OPT:

EXPR

E_EOL emit { TOK_0 }

OPT_EXEC_PARAM:

EXPR EXEC_PARAM_MORE emit { TOK_PUSH }

pass

EXEC_PARAM_MORE:

C_EXPR EXEC_PARAM_MORE

pass

EXEC_CALL:

"EXEc"

"@"

OPT_PROC_VAR:

VAR_WORD_SAVE OPT_PROC_VAR emit { TOK_POP, TOK_VAR_STORE } E_POP_VAR

pass

STATEMENT: statement

"." E_REM

"?" IO_CHAN_OPT PRINT_EOL IO_CHAN0

"PRInt" IO_CHAN_OPT PRINT_EOL IO_CHAN0

"INput" INPUT_STR INPUT_VAR_LIST IO_CHAN0

"GEt" GETK_EXPR

"PUt" IO_CHAN_OPT EXPR emit TOK_PUT IO_CHAN0

"CLS" IO_CHAN_OPT_NOCOMMA emit { TOK_BYTE_PUT, ATCLS } IO_CHAN0

"Poke" EXPR emit TOK_SADDR "," EXPR emit TOK_POKE

"Dpoke" EXPR emit TOK_SADDR "," EXPR emit TOK_DPOKE

"MSet" EXPR C_EXPR C_EXPR emit TOK_MSET

"Move" EXPR C_EXPR C_EXPR emit TOK_MOVE

"-move" EXPR C_EXPR C_EXPR emit TOK_NMOVE

"DO" E_EOL emit LT_DO_LOOP E_PUSH_LT

"Loop" E_EOL emit TOK_JUMP E_POP_LOOP

"Repeat" E_EOL emit LT_REPEAT E_PUSH_LT

"Until" FORCE_BOOL_EXPR emit TOK_CJUMP E_POP_REPEAT

"While" emit LT_WHILE_1 E_PUSH_LT FORCE_BOOL_EXPR emit { TOK_CJUMP, LT_WHILE_2 } E_PUSH_LT

"WEnd" E_EOL emit TOK_JUMP E_POP_WHILE

"If" FORCE_BOOL_EXPR emit { TOK_CJUMP, LT_IF } E_PUSH_LT THEN_OR_MULTILINE

"For" VAR_WORD_LVALUE_SADDR EQUAL emit TOK_PUSH EXPR emit TOK_DPOKE \

"To" EXPR STEP_OPTIONAL \

emit { TOK_FOR, TOK_CNJUMP, LT_FOR_2 } E_PUSH_LT emit LT_FOR_1 E_PUSH_LT

"Next" emit TOK_FOR_NEXT emit TOK_CJUMP NEXT_VARNAME E_EOL E_POP_FOR emit TOK_FOR_EXIT

"ELse" E_EOL emit TOK_JUMP emit LT_ELSE E_ELSEIF

"ELIf" emit { TOK_JUMP, LT_ELIF } E_ELSEIF FORCE_BOOL_EXPR emit { TOK_CJUMP, LT_IF } E_PUSH_LT

"Endif" E_EOL E_POP_IF

"EXit" emit TOK_JUMP E_EXIT_LOOP

"POSition" POSITION

"DIm" DIM_VAR DIM_MORE

"PAuse" PAUSE_OPT emit TOK_PAUSE

"INC" VAR_WORD_LVALUE_SADDR emit TOK_INC

"DEc" VAR_WORD_LVALUE_SADDR emit TOK_DEC

"PRoc" E_LABEL_CREATE emit { TOK_JUMP } E_LABEL_DEF emit LT_PROC_2 E_PUSH_LT OPT_PROC_VAR

"ENDProc" E_POP_PROC_2 emit TOK_RET E_POP_PROC_DATA

EXEC_CALL E_LABEL_CREATE OPT_EXEC_PARAM emit { TOK_CALL } E_DO_EXEC

"DAta" DATA_VAR DATA_END

"END" emit TOK_END

"Timer" emit { TOK_0, TOK_BYTE_POKE, RTCLOK1, TOK_0, TOK_BYTE_POKE, RTCLOK2 }

"CLR" emit { TOK_NUM, &CLEAR_DATA, TOK_USR_ADDR, TOK_USR_CALL }

LINE_ASSIGNMENT:

VAR_WORD_SAVE EQUAL EXPR emit TOK_VAR_STORE E_POP_VAR

VAR_WORD_LVALUE_SADDR EQUAL EXPR emit TOK_DPOKE

ARRAY_BYTE_ADDR emit TOK_SADDR EQUAL EXPR emit TOK_POKE

VAR_STR_LVALUE_SADDR EQUAL STR_EXPR emit TOK_COPY_STR

VAR_STR_LVALUE_SADDR EQUAL "+" STR_EXPR emit TOK_CAT_STR

pass

PARSE_START:

STATEMENT E_EOL

LINE_ASSIGNMENT E_EOL