JaM.mesa

Last edited by:

DIRECTORY

JaM: CEDAR DEFINITIONS

= BEGIN

Types

ROPE: TYPE = Rope.ROPE;

STREAM: TYPE = IO.STREAM;

State: TYPE = REF StateRep;

StateRep: TYPE = RECORD[

Stack: TYPE = REF StackRep;

StackRep: TYPE;

Any: TYPE = REF ANY;

Command: TYPE = REF CommandRep;

CommandRep: TYPE = RECORD[name: ATOM, proc: PROC[State]];

Op: TYPE = REF OpRep;

OpRep: TYPE = RECORD[body: Any];

Dict: TYPE = REF DictRep;

DictRep: TYPE = RECORD[tab: SymTab, attach: LIST OF Dict];

SymTab: TYPE = REF SymTabRep;

SymTabRep: TYPE;

Array: TYPE = REF ArrayRep;

ArrayRep: TYPE = RECORD[start, length: NAT, seq: Sequence];

Sequence: TYPE = REF SequenceRep;

SequenceRep: TYPE = RECORD[SEQUENCE size: NAT OF Any];

Mark: TYPE = REF MarkRep;

MarkRep: TYPE = RECORD[m: INT];

Creating a new interpreter

Create: PROC[out: STREAM] RETURNS[State];

Stack operations

NewStack: PROC RETURNS[Stack];

Push: PROC[self: State, x: Any];

PushBool: PROC[self: State, x: BOOL];

PushInt: PROC[self: State, x: INT];

PushReal: PROC[self: State, x: REAL];

PushRope: PROC[self: State, x: ROPE] = INLINE { Push[self, x] };

PushStream: PROC[self: State, x: STREAM] = INLINE { Push[self, x] };

PushArray: PROC[self: State, x: Array] = INLINE { Push[self, x] };

PushDict: PROC[self: State, x: Dict] = INLINE { Push[self, x] };

Pop: PROC[self: State] RETURNS[Any];

PopBool: PROC[self: State] RETURNS[BOOL];

PopInt: PROC[self: State] RETURNS[INT];

PopReal: PROC[self: State] RETURNS[REAL];

PopRope: PROC[self: State] RETURNS[ROPE];

PopStream: PROC[self: State] RETURNS[STREAM];

PopArray: PROC[self: State] RETURNS[Array];

PopDict: PROC[self: State] RETURNS[Dict];

Copy: PROC[self: State, n: INT];

Roll: PROC[self: State, n, k: INT];

Index: PROC[self: State, i: INT] RETURNS[Any];

Count: PROC[self: State] RETURNS[INT];

PushMark: PROC[self: State, m: INT ← 0];

PopMark: PROC[self: State, m: INT ← 0];

CountToMark: PROC[self: State, m: INT ← 0] RETURNS[INT];

Array operations

NewArray: PROC[length: INT] RETURNS[Array];

MakeArray: PROC[self: State, length: INT] RETURNS[Array];

SubArray: PROC[array: Array, start, length: INT] RETURNS[Array];

PutArray: PROC[from: Array, start: INT, into: Array];

APut: PROC[array: Array, i: INT, x: Any];

AGet: PROC[array: Array, i: INT] RETURNS[Any];

AFind: PROC[array: Array, x: Any] RETURNS[found: BOOL, i: INT];

ABind: PROC[array: Array, dict: Dict];

Dictionary operations

sysDict: Dict;

NewDict: PROC[length: INT] RETURNS[Dict];

DictLength: PROC[dict: Dict] RETURNS[INT];

Put: PROC[dict: Dict, key, val: Any];

TryToGet: PROC[dict: Dict, key: Any] RETURNS[found: BOOL, val: Any];

Get: PROC[dict: Dict, key: Any] RETURNS[Any];

Del: PROC[dict: Dict, key: Any];

AttachDict: PROC[dict, adict: Dict];

DetachDict: PROC[dict, adict: Dict];

DetachAll: PROC[dict: Dict];

Def: PROC[self: State, key, val: Any];

Store: PROC[self: State, key, val: Any];

TryToLoad: PROC[self: State, key: Any] RETURNS[found: BOOL, val: Any];

Load: PROC[self: State, key: Any] RETURNS[Any];

Where: PROC[self: State, key: Any] RETURNS[found: BOOL, where: Dict];

Begin: PROC[self: State, dict: Dict];

End: PROC[self: State];

Atoms

AtomToRope: PROC[ATOM] RETURNS[ROPE];

RopeToAtom: PROC[ROPE] RETURNS[ATOM];

Key comparison

Equal: PROC[a, b: Any] RETURNS[BOOL];

Eq: PROC[a, b: Any] RETURNS[BOOL] = INLINE { RETURN[IF a=b THEN TRUE ELSE Equal[a, b]] };

JaM will raise Error if any problems are encountered. The main execution loop converters these errors to ropes and prints them on the state.out stream since the main client of these procedures is the JaM typescript. It then raises the ERROR Stop. All clients of ExecuteRope and Execute may see the error Stop. If you are the top level procedure, it is adequate to immediately continue ie: Execute[state, any ! Stop => CONTINUE].

Scanning

ExecuteRope: PROC[self: State, rope: ROPE];

LineComplete: PROC[text: ROPE] RETURNS[BOOL];

Execution

Execute: PROC[self: State, x: Any];

GetAbort: PROC[self: State] RETURNS[BOOL];

SetAbort: PROC[self: State, b: BOOL];

Errors

ErrorType: TYPE = {AttachmentCycle, BoundsFault, DictionaryUnderflow, InvalidArgs, LoadFailed, NotAttached, NumericOverflow, OpenFailed, StackOverflow, StackUnderflow, UndefinedKey, Unimplemented, WrongMark, WrongType};

Error: ERROR[type: ErrorType, msg: Rope.ROPE ← NIL];

Exit: ERROR;

Stop: ERROR;

Registration (JaMControlImpl)

There is a global list of names and initialization procedures kept in sysDict called .initprocs. Each program that wants to register commands with JaM should register an initialization procedure and a unique name (capitalization counts).

There is a separate JaM dictionary for each typescript. To register commands in a particular dictionary execute (name) .callinit. This calls the named initialization proc with the correct JaM State.

Note: you can create your own State independent of the typescripts by using JaM.Create. You can then register commands in that dictionary directly or simulate the typescript mechanism with ExecuteRope[state, "(name) .callinit \n"];

RegisterInit: PROC[name: ROPE, init: PROC[State]];

Register: PROC[self: State, name: ROPE, proc: PROC[State]];

END.