Claude Code transcript - page 1/2

{"body":"Conway Life example program from Programming in occam2 for study of transpiler compatibility","merged":true,"state":"closed","title":"Add Conway Life example program from Programming in occam2","user":"dboreham"}

historical-examples/life.occ

     1→--  Code copied from Programming in occam®2
     2→--  © Geraint Jones, Michael Goldsmith 1988, 2001.
     3→--  Permission is granted to copy this material for private study; for other uses please contact occam-book@comlab.ox.ac.uk
     4→--
     5→--  The program in this chapter plays Life on a terminal screen.
     6→--
     7→
     8→--
     9→--  configuration constants
    10→--
    11→
    12→VAL INT array.width  IS 20 :   -- number of cells across the board
    13→VAL INT array.height IS 20 :   -- number of cells down the board
    14→
    15→VAL INT radius     IS 1 :       -- of the `sphere of influence'
    16→VAL INT diameter   IS (2 * radius) + 1 :
    17→VAL INT neighbours IS (diameter * diameter) - 1 :
    18→
    19→VAL INT number.of.cells IS array.height * array.width :
    20→VAL INT number.of.links IS neighbours * number.of.cells :
    21→
    22→--
    23→--  protocols
    24→--
    25→
    26→PROTOCOL STATE IS BOOL :
    27→
    28→VAL BOOL alive IS TRUE :
    29→VAL BOOL dead  IS NOT alive :
    30→
    31→PROTOCOL COMMAND
    32→  CASE
    33→    set.state; BOOL
    34→    evolve
    35→    terminate
    36→:
    37→
    38→PROTOCOL RESPONSE IS BOOL; BOOL :
    39→--
    40→--  cell processes
    41→--
    42→
    43→PROC broadcast.present.state([][][]CHAN OF STATE link,
    44→                             VAL INT x, y, VAL BOOL state )
    45→  PAR d = 0 FOR neighbours
    46→    link[x][y][d] ! state
    47→:
    48→
    49→PROC calculate.next.state([][][]CHAN OF STATE link,
    50→                          VAL []INT nx, ny,
    51→                          VAL BOOL state, BOOL next.state )
    52→  INT count :       -- number of living neighbours
    53→  SEQ
    54→    [neighbours]BOOL state.of.neighbour :
    55→    SEQ
    56→      PAR d = 0 FOR neighbours
    57→        link[nx[d]][ny[d]][d] ? state.of.neighbour[d]
    58→      count := 0
    59→      SEQ d = 0 FOR neighbours
    60→        IF
    61→          state.of.neighbour[d] = alive
    62→            count := count + 1
    63→          state.of.neighbour[d] = dead
    64→            SKIP
    65→    IF
    66→      count < 2     -- death from isolation
    67→        next.state := dead
    68→      count = 2     -- this cell is stable
    69→        next.state := state
    70→      count = 3     -- stable if alive, a birth if dead
    71→        next.state := alive
    72→      count > 3     -- death from overcrowding
    73→        next.state := dead
    74→:
    75→
    76→
    77→
    78→
    79→
    80→
    81→
    82→
    83→
    84→
    85→
    86→
    87→
    88→
    89→
    90→PROC cell([][][]CHAN OF STATE link,
    91→          VAL INT x, y, VAL []INT nx, ny,
    92→          CHAN OF COMMAND control,
    93→          CHAN OF RESPONSE sense         )
    94→  BOOL state, not.finished :
    95→  SEQ
    96→    state := dead       -- the whole board starts off dead
    97→    not.finished := TRUE
    98→    WHILE not.finished
    99→      control ? CASE
   100→
   101→        set.state; state
   102→          SKIP          -- state has been set to the new value
   103→
   104→        evolve
   105→          BOOL next.state :
   106→          SEQ
   107→            PAR
   108→              broadcast.present.state(link, x, y, state)
   109→              SEQ
   110→                calculate.next.state(link, nx, ny,
   111→                                     state, next.state )
   112→                sense ! (state <> next.state); next.state
   113→            state := next.state
   114→
   115→        terminate
   116→          not.finished := FALSE
   117→:
   118→
   119→--
   120→--  terminal-dependent output routines
   121→--
   122→
   123→PROC clear.screen(CHAN OF BYTE terminal)
   124→  -- clear screen sequence for an ANSI terminal
   125→  write.string(terminal, "*#1B[2J")
   126→:
   127→
   128→PROC move.cursor(CHAN OF BYTE terminal, VAL INT x, y)
   129→  -- left-handed co-ordinates, origin 0,0 at top left
   130→  CHAN OF DATA.ITEM c :
   131→  PAR
   132→    write.formatted(terminal, "*#1B[%d;%dH", c)
   133→    SEQ
   134→      c ! data.int; y + 1
   135→      c ! data.int; x + 1
   136→:
   137→
   138→
   139→
   140→
   141→--
   142→--  display routines
   143→--
   144→
   145→PROC initialize.display(CHAN OF BYTE screen)
   146→  -- display an entirely dead board
   147→  clear.screen(screen)
   148→:
   149→
   150→PROC clean.up.display(CHAN OF BYTE screen)
   151→  move.cursor(screen, 0, array.height)
   152→:
   153→
   154→PROC display.state(CHAN OF BYTE screen, VAL INT x, y, VAL BOOL state)
   155→  SEQ
   156→    move.cursor(screen, x, y)
   157→    IF
   158→      state = alive
   159→        screen ! '**'
   160→      state = dead
   161→        screen ! '*s'
   162→:
   163→
   164→--
   165→--  controller states
   166→--
   167→
   168→VAL INT idle         IS 0 :  -- controller activity values
   169→VAL INT editing      IS 1 :
   170→VAL INT single.step  IS 2 :
   171→VAL INT free.running IS 3 :
   172→VAL INT terminated   IS 4 :
   173→
   174→
   175→INT FUNCTION new.activity(VAL BYTE char)
   176→  INT activity :
   177→  VALOF
   178→    CASE char     -- typed on the keyboard ...
   179→      'q', 'Q'              -- ... Q to finish program
   180→        activity := terminated
   181→      's', 'S'              -- ... S to halt evolution
   182→        activity := idle
   183→      'e', 'E'              -- ... E to start editing
   184→        activity := editing
   185→      'r', 'R'              -- ... R to start evolution
   186→        activity := free.running
   187→      ELSE  -- ... or anything else for one generation
   188→        activity := single.step
   189→    RESULT activity
   190→:
   191→
   192→PROC display.activity(CHAN OF BYTE screen, VAL INT activity)
   193→  SEQ
   194→    move.cursor(screen, array.width+1, array.height/2)
   195→    CASE activity
   196→      idle
   197→        write.string(screen, "Idle")
   198→      editing
   199→        write.string(screen, "Edit")
   200→      single.step
   201→        write.string(screen, "Step")
   202→      free.running
   203→        write.string(screen, "Busy")
   204→      terminated
   205→        write.string(screen, "Done")
   206→:
   207→
   208→--
   209→--  generation
   210→--
   211→
   212→PROC generation(CHAN OF BYTE screen,
   213→                [][]CHAN OF COMMAND control,
   214→                [][]CHAN OF RESPONSE sense,
   215→                BOOL active                 )
   216→  SEQ
   217→    PAR x = 0 FOR array.width
   218→      PAR y = 0 FOR array.height
   219→        control[x][y] ! evolve
   220→    active := FALSE
   221→    SEQ x = 0 FOR array.width
   222→      SEQ y = 0 FOR array.height
   223→        BOOL changed, next.state :
   224→        SEQ
   225→          sense[x][y] ? changed; next.state
   226→          IF
   227→            changed
   228→              SEQ
   229→                display.state(screen, x, y, next.state)
   230→                active := TRUE
   231→            NOT changed
   232→              SKIP
   233→:
   234→
   235→
   236→
   237→
   238→
   239→
   240→
   241→
   242→
   243→--
   244→--  editor
   245→--
   246→
   247→INT FUNCTION min(VAL INT a, b)
   248→  INT min :
   249→  VALOF
   250→    IF
   251→      a <= b
   252→        min := a
   253→      b <= a
   254→        min := b
   255→    RESULT min
   256→:
   257→
   258→INT FUNCTION max(VAL INT a, b)
   259→  INT max :
   260→  VALOF
   261→    IF
   262→      a >= b
   263→        max := a
   264→      b >= a
   265→        max := b
   266→    RESULT max
   267→:
   268→
   269→
   270→
   271→
   272→
   273→
   274→
   275→
   276→
   277→
   278→
   279→
   280→
   281→
   282→
   283→
   284→
   285→
   286→
   287→
   288→
   289→
   290→
   291→
   292→
   293→
   294→PROC editor(CHAN OF BYTE keyboard, screen,
   295→            [][]CHAN OF COMMAND control   )
   296→  INT x, y :
   297→  BOOL editing :
   298→  SEQ
   299→    -- initialize co-ordinates to centre of board
   300→    x, y := array.width / 2, array.height / 2
   301→    editing := TRUE
   302→    WHILE editing
   303→      BYTE char :
   304→      SEQ
   305→        move.cursor(screen, x, y)
   306→        keyboard ? char
   307→        CASE char
   308→          'A'        -- move up, if possible
   309→            y := max(y - 1, 0)
   310→          'B'        -- move down, if possible
   311→            y := min(y + 1, array.height - 1)
   312→          'C'        -- move right, if possible
   313→            x := min(x + 1, array.width - 1)
   314→          'D'        -- move left, if possible
   315→            x := max(x - 1, 0)
   316→          '*s', '**'
   317→            VAL BOOL state IS (char = '**') = alive :
   318→            PAR
   319→              control[x][y] ! set.state; state
   320→              display.state(screen, x, y, state)
   321→          'q', 'Q'
   322→            editing := FALSE
   323→          ELSE
   324→            SKIP     -- ignore anything else
   325→:
   326→
   327→
   328→
   329→
   330→
   331→
   332→
   333→
   334→
   335→
   336→
   337→
   338→
   339→
   340→
   341→
   342→
   343→
   344→
   345→--
   346→--  controller
   347→--
   348→
   349→PROC controller(CHAN OF BYTE keyboard, screen,
   350→                [][]CHAN OF COMMAND control,
   351→                [][]CHAN OF RESPONSE sense    )
   352→  INT activity :
   353→  SEQ
   354→    activity := idle
   355→    initialize.display(screen)
   356→    WHILE activity <> terminated
   357→      SEQ
   358→        display.activity(screen, activity)
   359→        BYTE char :
   360→        PRI ALT
   361→          (activity <> editing) & keyboard ? char
   362→            activity := new.activity(char)
   363→          (activity <> idle) & SKIP
   364→            CASE activity
   365→              editing
   366→                SEQ
   367→                  editor(keyboard, screen, control)
   368→                  activity := idle
   369→              free.running, single.step
   370→                BOOL changing :
   371→                SEQ
   372→                  generation(screen, control, sense, changing)
   373→                  IF
   374→                    (activity = single.step) OR (NOT changing)
   375→                      activity := idle
   376→                    (activity = free.running) AND changing
   377→                      SKIP
   378→    display.activity(screen, activity)
   379→    PAR x = 0 FOR array.width
   380→      PAR y = 0 FOR array.height
   381→        control[x][y] ! terminate
   382→    clean.up.display(screen)
   383→:
   384→
   385→
   386→
   387→
   388→
   389→
   390→
   391→
   392→
   393→
   394→
   395→
   396→--
   397→--  structure of the program
   398→--
   399→
   400→[array.width][array.height][neighbours]CHAN OF STATE link :
   401→[array.width][array.height]CHAN OF COMMAND control :
   402→[array.width][array.height]CHAN OF RESPONSE sense :
   403→PAR
   404→  controller(terminal.keyboard, terminal.screen, control, sense)
   405→  PAR x = 0 FOR array.width
   406→    PAR y = 0 FOR array.height
   407→      VAL INT left  IS ((x - 1) + array.width)  \ array.width  :
   408→      VAL INT right IS  (x + 1)                 \ array.width  :
   409→      VAL INT up    IS  (y + 1)                 \ array.height :
   410→      VAL INT down  IS ((y - 1) + array.height) \ array.height :
   411→      VAL [neighbours]INT nx IS
   412→            [ right, x,    left, left, left, x,  right, right ] :
   413→      VAL [neighbours]INT ny IS
   414→            [ down,  down, down, y,    up,   up, up,    y     ] :
   415→      cell(link, x, y, nx, ny, control[x][y], sense[x][y])
   416→
   417→

[
  {
    "type": "text",
    "text": "Confirmed: Parenthesized guard expressions in ALT are also not supported. The parser only accepts `IDENT`, `TRUE`, or `FALSE` as the first token in an ALT case.\n\nNow I have a complete picture. Let me compile the analysis.\n\n---\n\nHere is the full categorization of distinct unsupported features causing parse errors in `/home/david/projects/code-associates/occam2go/historical-examples/life.occ`:\n\n---\n\n## Feature 1: Protocol declaration trailing colon\n\n**Lines:** 26, 36, 38 (and cascading to lines 47, 74, 117, 233, 325, 383)\n\n**Occam2 syntax:**\n```\nPROTOCOL STATE IS BOOL :\nPROTOCOL RESPONSE IS BOOL; BOOL :\nPROTOCOL COMMAND\n  CASE\n    set.state; BOOL\n    evolve\n    terminate\n:\n```\n\n**Problem:** The parser does not consume the optional trailing `:` on protocol declarations. The `parseProtocolDecl()` function (at `/home/david/projects/code-associates/occam2go/parser/parser.go` line 844) returns after parsing the type list or variant block, but never looks for or consumes a trailing colon. Without the colon, protocols parse fine (confirmed by existing tests). The trailing colon is valid occam2 syntax and used throughout the book's code.\n\n**Expected Go output:** Same as without the colon -- `type _proto_STATE = bool`, `type _proto_RESPONSE struct { _0 bool; _1 bool }`, etc. The colon is just a terminator that should be consumed and ignored.\n\n**Known gap?** Not listed in TODO.md. The CLAUDE.md mentions \"KRoC-style colon terminators on PROC/FUNCTION (optional)\" but does not mention the same for PROTOCOL declarations. This is a small parser fix -- add colon consumption in `parseProtocolDecl()` for both the IS form and variant form.\n\n---\n\n## Feature 2: Multi-dimensional arrays\n\n**Lines:** 43, 46, 49, 57, 90, 213-214, 219, 225, 295, 319, 350-351, 381, 400-402, 415\n\n**Occam2 syntax (declarations):**\n```\n[array.width][array.height][neighbours]CHAN OF STATE link :\n[array.width][array.height]CHAN OF COMMAND control :\n[array.width][array.height]CHAN OF RESPONSE sense :\n```\n\n**Occam2 syntax (proc parameters):**\n```\nPROC broadcast.present.state([][][]CHAN OF STATE link, ...)\nPROC cell([][][]CHAN OF STATE link, ...)\nPROC generation([][]CHAN OF COMMAND control, [][]CHAN OF RESPONSE sense, ...)\nPROC editor([][]CHAN OF COMMAND control)\nPROC controller([][]CHAN OF COMMAND control, [][]CHAN OF RESPONSE sense)\n```\n\n**Occam2 syntax (indexing):**\n```\nlink[x][y][d] ! state\nlink[nx[d]][ny[d]][d] ? state.of.neighbour[d]\ncontrol[x][y] ! evolve\nsense[x][y] ? changed; next.state\n```\n\n**Problem:** The parser only supports single-dimensional arrays (`[n]TYPE`, `[n]CHAN OF TYPE`) and single-level indexing (`arr[i]`). Multi-dimensional declarations like `[w][h]TYPE` and multi-level indexing like `arr[x][y]` are not recognized. This is the single most pervasive error source in this file.\n\n**Expected Go output:**\n```go\n// Declarations\nlink := make([][][]chan bool, array_width)   // 3D channel array with init loops\ncontrol := make([][]chan _proto_COMMAND, array_width)  // 2D\n\n// Proc parameters\nfunc broadcast_present_state(link [][][]chan bool, ...)\nfunc generation(control [][]chan _proto_COMMAND, sense [][]chan _proto_RESPONSE, ...)\n\n// Indexing\nlink[x][y][d] <- state\ncontrol[x][y] <- _proto_COMMAND_evolve{}\n```\n\n**Known gap?** Not explicitly listed in TODO.md. This is a significant feature requiring changes across parser (array declarations, proc params, indexed operations) and codegen (multi-dimensional initialization, multi-level index expressions).\n\n---\n\n## Feature 3: CASE with comma-separated match values\n\n**Lines:** 179, 181, 183, 185, 316, 321, 369\n\n**Occam2 syntax:**\n```\nCASE char\n  'q', 'Q'\n    activity := terminated\n  's', 'S'\n    activity := idle\n  ELSE\n    activity := single.step\n\nCASE char\n  '*s', '**'\n    ...\n  'q', 'Q'\n    editing := FALSE\n\nCASE activity\n  free.running, single.step\n    ...\n```\n\n**Problem:** The `parseCaseStatement()` function (line 2579 of parser.go) only parses a single expression per case arm (`choice.Values = append(choice.Values, p.parseExpression(LOWEST))`). It does not loop to check for commas and parse additional values. The AST `CaseChoice` struct already has a `Values []Expression` slice, so it was designed for this but never implemented.\n\n**Expected Go output:**\n```go\nswitch char {\ncase 'q', 'Q':\n    activity = terminated\ncase 's', 'S':\n    activity = idle\ndefault:\n    activity = single_step\n}\n```\n\n**Known gap?** Not listed in TODO.md. The parser's `CaseChoice.Values` slice is already designed for multiple values, so this should be a straightforward parser change to loop on commas. CASE ELSE already works correctly (confirmed by testing) -- the ELSE errors in the error output are cascade failures from the comma parsing.\n\n---\n\n## Feature 4: PRI ALT (Priority ALT)\n\n**Lines:** 360\n\n**Occam2 syntax:**\n```\nPRI ALT\n  (activity <> editing) & keyboard ? char\n    activity := new.activity(char)\n  (activity <> idle) & SKIP\n    CASE activity\n      ...\n```\n\n**Problem:** `PRI` is not a recognized keyword in the lexer (`/home/david/projects/code-associates/occam2go/lexer/token.go`). It is lexed as an `IDENT` token. The parser then treats `PRI` as a procedure call and `ALT` as a separate statement. This generates incorrect Go code (`PRI()` followed by a `select`).\n\n**Expected Go output:** `PRI ALT` should map to Go `select {}` just like regular `ALT`. In Go, `select` already uses non-deterministic selection among ready cases, so there's no direct equivalent of priority. The simplest mapping is to treat `PRI ALT` identically to `ALT`. An alternative is to use a chain of `reflect.Select` with ordered cases, but for practical purposes treating it as `ALT` is acceptable.\n\n**Known gap?** YES -- listed in TODO.md under \"Other language features\": \"PRI ALT / PRI PAR -- Priority variants of ALT and PAR.\"\n\n---\n\n## Feature 5: SKIP guard in ALT (`condition & SKIP`)\n\n**Lines:** 363\n\n**Occam2 syntax:**\n```\n(activity <> idle) & SKIP\n  CASE activity\n    ...\n```\n\n**Problem:** The `parseAltCase()` function (line 1665 of parser.go) expects a channel name (IDENT) after `&` in a guarded ALT case. `SKIP` is a keyword, not an identifier, so it fails with \"expected channel name after guard, got SKIP\". A SKIP guard means \"this alternative is always ready\" -- it's essentially a default case that fires immediately if the guard condition is true.\n\n**Expected Go output:** This maps to a `default` case in a Go `select` statement (conditional on the guard). For example:\n```go\nselect {\ncase char = <-keyboard:\n    if activity != editing {\n        activity = new_activity(char)\n    }\ndefault:\n    if activity != idle {\n        // ... the body\n    }\n}\n```\n\nOr alternatively, the guard condition can be checked before entering the select, with the default case only present when the guard is true.\n\n**Known gap?** Not explicitly listed in TODO.md, but it is related to the PRI ALT entry. This is a specific ALT feature -- the \"SKIP guard\" pattern -- used for non-blocking alternatives.\n\n---\n\n## Feature 6: Parenthesized guard expressions in ALT\n\n**Lines:** 361, 363\n\n**Occam2 syntax:**\n```\n(activity <> editing) & keyboard ? char\n(activity <> idle) & SKIP\n```\n\n**Problem:** The `parseAltCase()` function at line 1689 only accepts `IDENT`, `TRUE`, or `FALSE` as the first token of an ALT case. Parenthesized expressions like `(activity <> editing)` start with `LPAREN`, which is rejected. The parser needs to accept general expressions (including parenthesized ones) as guard conditions.\n\n**Expected Go output:** The guard expression becomes a runtime boolean check. In combination with the ALT mapping:\n```go\n// Before the select, evaluate guards\n// Or wrap the case handler with if-guard\n```\n\n**Known gap?** Not listed in TODO.md. The current ALT implementation supports simple guards (`TRUE & channel ? x`, `identifier & channel ? x`) but not arbitrary expression guards.\n\n---\n\n## Feature 7: Multi-line abbreviation expressions (IS as continuation)\n\n**Lines:** 411-414\n\n**Occam2 syntax:**\n```\nVAL [neighbours]INT nx IS\n      [ right, x,    left, left, left, x,  right, right ] :\nVAL [neighbours]INT ny IS\n      [ down,  down, down, y,    up,   up, up,    y     ] :\n```\n\n**Problem:** The lexer's `isContinuationOp()` function (`/home/david/projects/code-associates/occam2go/lexer/lexer.go` line 418) does not include `IS` as a continuation operator. When `IS` appears at the end of a line, a NEWLINE token is emitted, and the next-line indented content is treated as a new block rather than a continuation of the expression. This causes \"unexpected token in expression: NEWLINE\".\n\n**Expected Go output:**\n```go\nnx := []int{right, x, left, left, left, x, right, right}\nny := []int{down, down, down, y, up, up, up, y}\n```\n\n**Known gap?** Not listed in TODO.md. The fix is to add `IS` to the `isContinuationOp()` function in the lexer, which would make the NEWLINE/INDENT suppression kick in automatically. However, `IS` is used in abbreviations (not a binary operator), so the approach may need to be slightly different -- perhaps checking `lastTokenType == IS` in the lexer's continuation logic.\n\n---\n\n## Summary Table\n\n| # | Feature | Lines | Cascade Errors | In TODO.md? | Estimated Complexity |\n|---|---------|-------|----------------|-------------|---------------------|\n| 1 | Protocol trailing colon | 26, 36, 38 | 47, 74, 117, 233, 325, 383 | No | Small (parser only) |\n| 2 | Multi-dimensional arrays | 43, 46, 49, 57, 90, 213, 219, 225, 295, 319, 350, 381, 400-402, 415 | Many | No | Large (parser + codegen) |\n| 3 | CASE comma-separated values | 179, 181, 183, 185, 316, 321, 369 | 187, 323 (ELSE cascade) | No | Small (parser only) |\n| 4 | PRI ALT | 360 | -- | **Yes** | Medium (lexer + parser) |\n| 5 | SKIP guard in ALT | 363 | -- | No (related to PRI ALT) | Medium (parser + codegen) |\n| 6 | Parenthesized ALT guards | 361, 363 | -- | No | Small (parser only) |\n| 7 | Multi-line abbreviation (IS continuation) | 411-414 | -- | No | Small (lexer only) |\n\n**Note on cascade errors:** The CASE ELSE errors (lines 187, 323) are NOT a separate feature gap. CASE ELSE already works correctly in isolation (confirmed by testing). The errors at those lines are cascading from the unrecognized comma-separated values on preceding CASE arms. Similarly, many errors from lines 99-116 (variant protocol receive) are cascades from Feature 1 (protocol trailing colon) -- once the `PROTOCOL COMMAND` declaration fails to parse, the variant receive `control ? CASE` cannot match it to a known protocol.\n\n**Additional notes on external dependencies:** Lines 123-136 reference `write.string`, `write.formatted`, `DATA.ITEM`, `data.int`, `terminal.keyboard`, `terminal.screen` -- these are library routines from the KRoC course module runtime. They are not parser issues but would need runtime library stubs or implementations to actually compile the transpiled output."
  },
  {
    "type": "text",
    "text": "agentId: ad5ce07783dcf1d58 (for resuming to continue this agent's work if needed)\n<usage>total_tokens: 58217\ntool_uses: 56\nduration_ms: 307839</usage>"
  }
]

https://github.com/codeassociates/occam2go/issues/73

https://github.com/codeassociates/occam2go/issues/74

https://github.com/codeassociates/occam2go/issues/75

https://github.com/codeassociates/occam2go/issues/76

https://github.com/codeassociates/occam2go/issues/77

https://github.com/codeassociates/occam2go/issues/78

https://github.com/codeassociates/occam2go/issues/79

{"url":"https://api.github.com/repos/codeassociates/occam2go/issues/comments/3945869818","html_url":"https://github.com/codeassociates/occam2go/pull/71#issuecomment-3945869818","issue_url":"https://api.github.com/repos/codeassociates/occam2go/issues/71","id":3945869818,"node_id":"IC_kwDORHYLFc7rMTH6","user":{"login":"associate-1","id":248367688,"node_id":"U_kgDODs3KSA","avatar_url":"https://avatars.githubusercontent.com/u/248367688?u=d59e4bbac3ab34986725118226e0a14b4069499e&v=4","gravatar_id":"","url":"https://api.github.com/users/associate-1","html_url":"https://github.com/associate-1","followers_url":"https://api.github.com/users/associate-1/followers","following_url":"https://api.github.com/users/associate-1/following{/other_user}","gists_url":"https://api.github.com/users/associate-1/gists{/gist_id}","starred_url":"https://api.github.com/users/associate-1/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/associate-1/subscriptions","organizations_url":"https://api.github.com/users/associate-1/orgs","repos_url":"https://api.github.com/users/associate-1/repos","events_url":"https://api.github.com/users/associate-1/events{/privacy}","received_events_url":"https://api.github.com/users/associate-1/received_events","type":"User","user_view_type":"public","site_admin":false},"created_at":"2026-02-23T16:34:30Z","updated_at":"2026-02-23T16:34:30Z","author_association":"MEMBER","body":"## Transpiler Compatibility Analysis\n\nAttempted to transpile `life.occ` and identified **7 unsupported features** that prevent it from parsing. Issues have been filed for each:\n\n| Issue | Feature | Complexity |\n|-------|---------|------------|\n| #73 | Protocol trailing colon terminator | Small |\n| #74 | Multi-dimensional arrays (decl, params, indexing) | **Large** |\n| #75 | CASE comma-separated match values and ELSE | Small |\n| #76 | PRI ALT (priority alternation) | Medium |\n| #77 | SKIP guard in ALT (`condition & SKIP`) | Medium |\n| #78 | Parenthesized guard expressions in ALT | Small |\n| #79 | Multi-line abbreviations (`IS` as continuation) | Small |\n\n**#74 (multi-dimensional arrays)** is the biggest gap — it accounts for the majority of parse errors and requires changes across parser, AST, and codegen. The four small issues (#73, #75, #78, #79) are straightforward parser/lexer fixes that could be knocked out quickly.\n\nNote: the program also depends on KRoC course module library routines (`write.string`, `write.formatted`, `terminal.keyboard`, `terminal.screen`) which would need stubs or implementations to compile the transpiled output.","reactions":{"url":"https://api.github.com/repos/codeassociates/occam2go/issues/comments/3945869818/reactions","total_count":0,"+1":0,"-1":0,"laugh":0,"hooray":0,"confused":0,"heart":0,"rocket":0,"eyes":0},"performed_via_github_app":null,"pin":null}

{"body":"A code example from the book \"Programming in Occam2\" has been added to this repo here: ./historical-examples/life.occ\n\nPlease analyze this program to determine why it doesn't parse and run with the current version of the transpiler.\n\n","state":"open","title":"Investigate transpiler compatibility with example program from the Occam2 book"}

{"url":"https://api.github.com/repos/codeassociates/occam2go/issues/comments/3945884124","html_url":"https://github.com/codeassociates/occam2go/issues/72#issuecomment-3945884124","issue_url":"https://api.github.com/repos/codeassociates/occam2go/issues/72","id":3945884124,"node_id":"IC_kwDORHYLFc7rMWnc","user":{"login":"associate-1","id":248367688,"node_id":"U_kgDODs3KSA","avatar_url":"https://avatars.githubusercontent.com/u/248367688?u=d59e4bbac3ab34986725118226e0a14b4069499e&v=4","gravatar_id":"","url":"https://api.github.com/users/associate-1","html_url":"https://github.com/associate-1","followers_url":"https://api.github.com/users/associate-1/followers","following_url":"https://api.github.com/users/associate-1/following{/other_user}","gists_url":"https://api.github.com/users/associate-1/gists{/gist_id}","starred_url":"https://api.github.com/users/associate-1/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/associate-1/subscriptions","organizations_url":"https://api.github.com/users/associate-1/orgs","repos_url":"https://api.github.com/users/associate-1/repos","events_url":"https://api.github.com/users/associate-1/events{/privacy}","received_events_url":"https://api.github.com/users/associate-1/received_events","type":"User","user_view_type":"public","site_admin":false},"created_at":"2026-02-23T16:36:30Z","updated_at":"2026-02-23T16:36:30Z","author_association":"MEMBER","body":"Analysis complete — see the detailed findings in [this comment on PR #71](https://github.com/codeassociates/occam2go/pull/71#issuecomment-3945869818).\n\nSeven unsupported features were identified and filed as individual issues: #73, #74, #75, #76, #77, #78, #79.","reactions":{"url":"https://api.github.com/repos/codeassociates/occam2go/issues/comments/3945884124/reactions","total_count":0,"+1":0,"-1":0,"laugh":0,"hooray":0,"confused":0,"heart":0,"rocket":0,"eyes":0},"performed_via_github_app":null,"pin":null}