ground-programs/programs/bf.grnd

# A Brainfuck interpreter in Ground (https://git.maxwellj.xyz/ground/ground) (https://en.wikipedia.org/wiki/Brainfuck)

stdout "Brainf*ck Code: "
stdin &str
stdout "Input: "
stdin &input
set &idx 0
setlist *cells 0
setlist *startloop
set &loopdepth 0
set &ignore false
set &selectedcell 0
set &inputidx 0
getstrsize $str &len

setlist *ascii ' ' '!' '"' '#' '$' '%' '&' "'" '(' ')' '*' '+' ',' '-' '.' '/' '0' '1' '2' '3' '4' '5' '6' '7' '8' '9' ':' ';' '<' '=' '>' '?' '@' 'A' 'B' 'C' 'D' 'E' 'F' 'G' 'H' 'I' 'J' 'K' 'L' 'M' 'N' 'O' 'P' 'Q' 'R' 'S' 'T' 'U' 'V' 'W' 'X' 'Y' 'Z' '[' '\' ']' '^' '_' '`' 'a' 'b' 'c' 'd' 'e' 'f' 'g' 'h' 'i' 'j' 'k' 'l' 'm' 'n' 'o' 'p' 'q' 'r' 's' 't' 'u' 'v' 'w' 'x' 'y' 'z' '{' '|' '}' '~'

@loop
    equal $idx $len &store
    if $store %end

    getstrcharat $str $idx &idxchar
    
    equal $idxchar '+' &store
    if $store %plus

    equal $idxchar '-' &store
    if $store %minus

    equal $idxchar '>' &store
    if $store %right

    equal $idxchar '<' &store
    if $store %left

    equal $idxchar '[' &store
    if $store %leftbracket

    equal $idxchar ']' &store
    if $store %rightbracket

    equal $idxchar ',' &store
    if $store %input

    equal $idxchar '.' &store
    if $store %output

    jump %increment

    @plus
        if $ignore %increment
        lesser $selectedcell 0 &store
        if $store %rangeerror
        getlistat *cells $selectedcell &store
        add $store 1 &store
        setlistat *cells $selectedcell $store
        inequal $store 256 &store
        if $store %increment
        setlistat *cells $selectedcell 0
        jump %increment

    @minus
        if $ignore %increment
        lesser $selectedcell 0 &store
        if $store %rangeerror
        getlistat *cells $selectedcell &store
        subtract $store 1 &store
        setlistat *cells $selectedcell $store
        inequal $store -1 &store
        if $store %increment
        setlistat *cells $selectedcell 255
        jump %increment

    @right
        if $ignore %increment
        add $selectedcell 1 &selectedcell

        # Check if new cell needs to be added
        getlistsize *cells &store
        lesser $selectedcell $store &store
        if $store %increment
        listappend *cells 0
        jump %increment

    @left
        if $ignore %increment
        subtract $selectedcell 1 &selectedcell
        jump %increment

    @leftbracket
        if $ignore %customignoreleft
        listappend *startloop 0
        setlistat *startloop $loopdepth $idx
        set &ignoreidx $loopdepth
        add $loopdepth 1 &loopdepth

        getlistat *cells $selectedcell &store
        inequal $store 0 &store
        if $store %increment

        # If selected cell is 0, jump to the matching right bracket (by ignoring all other instructions)
        set &ignore true
        jump %increment

        @customignoreleft
        add $loopdepth 1 &loopdepth
        jump %increment

    @rightbracket
        subtract $loopdepth 1 &loopdepth
        if $ignore %continue
        getlistat *startloop $loopdepth &store
        set &idx $store
        # Don't increment
        jump %loop

        @continue
        inequal $loopdepth $ignoreidx &store
        if $store %increment
        set &ignore false
        jump %increment

    @input
        if $ignore %increment
        lesser $selectedcell 0 &store
        if $store %rangeerror
        
        getstrsize $input &store
        equal $inputidx $store &store
        if $store %inputzero

        getstrcharat $input $inputidx &inputstore
        tostring $inputstore &store
        equal $store "'" &store
        if $store %singlequote
        set &asciiidx 0
        @findascii
            getlistsize *ascii &store
            equal $store $asciiidx &store
            if $store %noascii

            equal $asciiidx 7 &store
            if $store %asciiincrement
            getlistat *ascii $asciiidx &store
            equal $store $inputstore &store
            if $store %exitascii
            @asciiincrement
            add $asciiidx 1 &asciiidx
            jump %findascii

        @exitascii
        add $asciiidx 32 &asciiidx
        setlistat *cells $selectedcell $asciiidx

        add $inputidx 1 &inputidx
        jump %increment

        @singlequote
        setlistat *cells $selectedcell 39
        add $inputidx 1 &inputidx
        jump %increment

        @inputzero
        setlistat *cells $selectedcell 0
        add $inputidx 1 &inputidx
        jump %increment

        @noascii
        error "Error: Invalid ASCII output code"

    @output
        if $ignore %increment
        lesser $selectedcell 0 &store
        if $store %rangeerror

        # 0-31 is not doing anything, except for 10 which is newline
        getlistat *cells $selectedcell &store
        equal $store 10 &store
        if $store %newline
        
        getlistat *cells $selectedcell &store
        lesser $store 32 &store
        if $store %blank

        getlistat *cells $selectedcell &store
        greater $store 126 &store
        if $store %blank

        getlistat *cells $selectedcell &store
        subtract $store 32 &store
        getlistat *ascii $store &store
        stdout $store
        jump %increment

        @newline
        stdlnout ""
        jump %increment

        @blank
        stdout " "
        jump %increment


    @increment
    add $idx 1 &idx
    jump %loop

    @rangeerror
    error "Cannot edit garbage data (negative cell index)"
@end

# Output list
stdlnout ""
getlistsize *cells &listlen
set &idx 0
stdout "["
@stdoutloop
    getlistat *cells $idx &store
    stdout $store
    add $idx 1 &idx
    equal $idx $listlen &store
    if $store %trueend
    stdout ", "
    jump %stdoutloop

@trueend
stdout "]"