src/interpreter/builtin_signatures.ts

@@ -1,106 +0,0 @@
-import { BadArgumentError } from '@/utils';
-import type { DenotableValueType } from '.';
-
-export type Signature = Array<Array<DenotableValueType | Signature>>;
-
-export const primitiveOperationSignatures: Record<string, Signature> = {
-  '+': [
-    ['int', 'int', 'int'],
-    ['real', 'real', 'real'],
-    ['int', 'real', 'real'],
-    ['real', 'int', 'real'],
-  ],
-  '-': [
-    ['int', 'int', 'int'],
-    ['real', 'real', 'real'],
-    ['int', 'real', 'real'],
-    ['real', 'int', 'real'],
-  ],
-  '*': [
-    ['int', 'int', 'int'],
-    ['real', 'real', 'real'],
-    ['int', 'real', 'real'],
-    ['real', 'int', 'real'],
-  ],
-  '/': [
-    ['int', 'int', 'int'],
-    ['real', 'real', 'real'],
-    ['int', 'real', 'real'],
-    ['real', 'int', 'real'],
-  ],
-  '%': [['int', 'int', 'int']],
-  '**': [
-    ['int', 'int', 'int'],
-    ['real', 'real', 'real'],
-    ['int', 'real', 'real'],
-    ['real', 'int', 'real'],
-  ],
-  '>>': [['int', 'int', 'int']],
-  '<<': [['int', 'int', 'int']],
-  '&': [['int', 'int', 'int']],
-  '|': [['int', 'int', 'int']],
-  '^': [['int', 'int', 'int']],
-  '==': [
-    ['int', 'int', 'int'],
-    ['real', 'real', 'int'],
-    ['string', 'string', 'int'],
-  ],
-  '!=': [
-    ['int', 'int', 'int'],
-    ['real', 'real', 'int'],
-    ['string', 'string', 'int'],
-  ],
-  '<': [
-    ['int', 'int', 'int'],
-    ['real', 'real', 'int'],
-  ],
-  '>': [
-    ['int', 'int', 'int'],
-    ['real', 'real', 'int'],
-  ],
-  '<=': [
-    ['int', 'int', 'int'],
-    ['real', 'real', 'int'],
-  ],
-  '>=': [
-    ['int', 'int', 'int'],
-    ['real', 'real', 'int'],
-  ],
-  '&&': [['int', 'int', 'int']],
-  '||': [['int', 'int', 'int']],
-  '!': [['int', 'int']],
-};
-
-export const getResultingType = (
-  opr: string,
-  types: DenotableValueType[],
-): DenotableValueType | Signature => {
-  const signature = primitiveOperationSignatures[opr];
-  if (!signature) {
-    throw new BadArgumentError(`Invalid operation: ${opr}`);
-  }
-
-  const resultingType = signature.find(sig => {
-    if (sig.length !== types.length) {
-      return false;
-    }
-
-    return sig.every((type, i) => {
-      if (Array.isArray(type)) {
-        return getResultingType(
-          opr,
-          types.map((t, j) => (i === j ? t : 'int')),
-        );
-      }
-      return type === 'int' || type === types[i];
-    });
-  });
-
-  if (!resultingType) {
-    throw new TypeError(
-      `Invalid types for operation ${opr}: ${types.join(', ')}`,
-    );
-  }
-
-  return resultingType as DenotableValueType | Signature;
-};

src/interpreter/builtins.ts

@@ -0,0 +1,94 @@
+import { type DenotableFunctionSignature, Environment } from '.';
+
+const addUnaryIntegerOperationsTo = (env: Environment) => {
+  const unaryIntegerOperationSignatures: DenotableFunctionSignature[] = [
+    {
+      arguments: ['int'],
+      return: 'int',
+    },
+  ];
+
+  for (const { name, fn } of [
+    { name: '~', fn: (a: number) => ~a },
+    { name: '!', fn: (a: number) => (!a ? 1 : 0) },
+  ]) {
+    env.set(name, {
+      type: 'function',
+      value: { signatures: unaryIntegerOperationSignatures, body: fn },
+    });
+  }
+
+  return env;
+};
+
+const addBinaryIntegerOperationsTo = (env: Environment) => {
+  const binaryIntegerOperationSignatures: DenotableFunctionSignature[] = [
+    {
+      arguments: ['int', 'int'],
+      return: 'int',
+    },
+  ];
+
+  for (const { name, fn } of [
+    { name: '%', fn: (a: number, b: number) => a % b },
+    { name: '>>', fn: (a: number, b: number) => a >> b },
+    { name: '<<', fn: (a: number, b: number) => a << b },
+    { name: '|', fn: (a: number, b: number) => a | b },
+    { name: '^', fn: (a: number, b: number) => a ^ b },
+    { name: '&&', fn: (a: number, b: number) => (a && b ? 1 : 0) },
+    { name: '<=', fn: (a: number, b: number) => (a <= b ? 1 : 0) },
+    { name: '<', fn: (a: number, b: number) => (a < b ? 1 : 0) },
+    { name: '>', fn: (a: number, b: number) => (a > b ? 1 : 0) },
+    { name: '>=', fn: (a: number, b: number) => (a >= b ? 1 : 0) },
+    { name: '||', fn: (a: number, b: number) => (a || b ? 1 : 0) },
+    { name: '==', fn: (a: number, b: number) => (a == b ? 1 : 0) },
+  ]) {
+    env.set(name, {
+      type: 'function',
+      value: { signatures: binaryIntegerOperationSignatures, body: fn },
+    });
+  }
+
+  return env;
+};
+
+const addBinaryArithmeticOperationsTo = (env: Environment) => {
+  const binaryArithmeticSignatures: DenotableFunctionSignature[] = [
+    {
+      arguments: ['int', 'int'],
+      return: 'int',
+    },
+    {
+      arguments: [
+        ['int', 'real'],
+        ['int', 'real'],
+      ],
+      return: 'real',
+    },
+  ];
+
+  for (const { name, fn } of [
+    { name: '+', fn: (a: number, b: number) => a + b },
+    { name: '-', fn: (a: number, b: number) => a - b },
+    { name: '*', fn: (a: number, b: number) => a * b },
+    { name: '/', fn: (a: number, b: number) => a / b },
+    { name: '**', fn: (a: number, b: number) => a ** b },
+  ]) {
+    env.set(name, {
+      type: 'function',
+      value: { signatures: binaryArithmeticSignatures, body: fn },
+    });
+  }
+
+  return env;
+};
+
+export const environmentWithBuiltins = () => {
+  const environment = new Environment();
+
+  return [
+    addBinaryArithmeticOperationsTo,
+    addBinaryIntegerOperationsTo,
+    addUnaryIntegerOperationsTo,
+  ].reduce((acc, builtinsAdder) => builtinsAdder(acc), environment);
+};

src/interpreter/denotable.ts

@@ -0,0 +1,71 @@
+import type { Identifier } from '@/parser';
+
+export type UnionDenotableType =
+  | Array<DenotableType | DenotableFunctionSignature>
+  | DenotableType
+  | DenotableFunctionSignature;
+
+export type DenotableFunctionSignature = {
+  arguments: Array<UnionDenotableType>;
+  return: UnionDenotableType;
+};
+
+export type DenotableFunction = {
+  signatures: Array<DenotableFunctionSignature>;
+  body: Function;
+};
+
+export type DenotableType =
+  | 'null'
+  | 'int'
+  | 'real'
+  | 'string'
+  | 'bytearray'
+  | 'function'
+  | 'reference';
+
+export type DenotableValue =
+  | null
+  | number
+  | string
+  | Uint8Array
+  | DenotableFunction
+  | Identifier;
+
+export type Denotable = {
+  type: DenotableType;
+  value: DenotableValue;
+};
+
+export const functionSignaturesEqual = (
+  a: DenotableFunctionSignature,
+  b: DenotableFunctionSignature,
+): boolean => {
+  if (a.arguments.length !== b.arguments.length) {
+    return false;
+  }
+
+  if (typeof a.return !== typeof b.return) {
+    return false;
+  }
+
+  if (
+    typeof a.return === 'object' &&
+    typeof b.return === 'object' &&
+    'return' in a.return &&
+    'return' in b.return
+  ) {
+    return functionSignaturesEqual(a.return, b.return);
+  }
+};
+
+export const matchSignature = (
+  args: Array<DenotableFunction | DenotableType>,
+  signatures: Array<DenotableFunctionSignature>,
+): DenotableFunctionSignature | undefined => {
+  return signatures.find(signature => {
+    if (args.length !== signature.arguments.length) {
+      return false;
+    }
+  });
+};

src/interpreter/environment.ts

@@ -1,8 +1,14 @@
-import { UnknownSymbolError } from '@/utils';
+import { UnknownSymbolError, InvalidType } from '@/utils';
-import type { DenotableValue } from '.';
+import type {
+  Denotable,
+  DenotableFunction,
+  DenotableFunctionSignature,
+  DenotableType,
+  DenotableValue,
+} from '.';
 
 export class Environment {
-  private scope: Map<string, DenotableValue>;
+  private scope: Map<string, Denotable>;
   private parent: Environment | null;
 
   constructor(parent: Environment | null = null) {
@@ -10,13 +16,13 @@ export class Environment {
     this.scope = new Map();
   }
 
-  public set(name: string, value: DenotableValue) {
+  public set(name: string, value: Denotable) {
     this.scope.set(name, value);
   }
 
-  public get(name: string): DenotableValue {
+  public get(name: string): Denotable {
     if (this.scope.has(name)) {
-      return this.scope.get(name);
+      return this.scope.get(name)!;
     }
 
     if (this.parent) {
@@ -41,4 +47,13 @@ export class Environment {
   public createChild(): Environment {
     return new Environment(this);
   }
+
+  public apply(name: string, args: Denotable[]): Denotable {
+    const fn = this.get(name);
+    if (typeof fn.value !== 'object' || !fn.value || !('body' in fn.value)) {
+      throw new InvalidType(name + ' is not a valid function');
+    }
+
+    return { type: 'real', value: 0 };
+  }
 }

src/interpreter/index.ts

@@ -1,11 +1,3 @@
-export type DenotableValueType =
+export * from './denotable';
-  | 'null'
-  | 'int'
-  | 'real'
-  | 'string'
-  | 'function'
-  | 'reference';
-export type DenotableValue = { type: DenotableValueType; value: any };
-
 export * from './environment';
 export * from './interpreter';

src/interpreter/interpreter.ts

@@ -4,7 +4,7 @@ import {
   type Program,
   type Value,
 } from '@/parser';
-import { Environment, type DenotableValue } from '.';
+import { Environment, type Denotable } from '.';
 import {
   BadArgumentError,
   InvalidStateError,
@@ -16,7 +16,7 @@ const evaluateValue = (
   value: Value,
   env: Environment,
   logger: TracingLogger,
-): DenotableValue => {
+): Denotable => {
   if (typeof value === 'string') {
     return { type: 'string', value };
   }
@@ -49,50 +49,8 @@ const evaluatePrimitiveOperation = (
     evaluateValue(operand, env, logger.createChild('evaluteValue')),
   );
 
-  const rightReducingOperations = {
+  let result: Denotable = { type: 'null', value: null };
-    '+': (acc: number, operand: { value: number }) => acc + operand.value,
-    '-': (acc: number, operand: { value: number }) => acc - operand.value,
-    '*': (acc: number, operand: { value: number }) => acc * operand.value,
-  };
-  const leftReducingOperations = {
-    '/': (acc: number, operand: { value: number }) => acc / operand.value,
-    '%': (acc: number, operand: { value: number }) => acc % operand.value,
-    '**': (acc: number, operand: { value: number }) => acc ** operand.value,
-    '>>': (acc: number, operand: { value: number }) => acc >> operand.value,
-    '<<': (acc: number, operand: { value: number }) => acc << operand.value,
-    '&': (acc: number, operand: { value: number }) => acc & operand.value,
-    '|': (acc: number, operand: { value: number }) => acc | operand.value,
-    '^': (acc: number, operand: { value: number }) => acc ^ operand.value,
-  };
-  const someNumberIsReal = operandValues.some(({ type }) => type === 'real');
-
-  let result: DenotableValue = { type: 'null', value: null };
   const continuationEnvironment = env.createChild();
-  if (opr in rightReducingOperations) {
-    logger.debug('Evaluating right reducing operation: ' + opr);
-    const sum = operandValues.reduce(
-      rightReducingOperations[opr as keyof typeof rightReducingOperations],
-      0,
-    );
-    result = { type: someNumberIsReal ? 'real' : 'int', value: sum };
-
-    for (const binding of resultBindings) {
-      continuationEnvironment.set(binding.name, result);
-    }
-  }
-  if (opr in leftReducingOperations) {
-    logger.debug('Evaluating left reducing operation: ' + opr);
-    const [first, ...rest] = operandValues;
-    const sum = rest.reduce(
-      leftReducingOperations[opr as keyof typeof leftReducingOperations],
-      first.value,
-    );
-    result = { type: someNumberIsReal ? 'real' : 'int', value: sum };
-
-    for (const binding of resultBindings) {
-      continuationEnvironment.set(binding.name, result);
-    }
-  }
 
   // return the result of the last continuation
   return continuations.reduce((_, continuation, i) => {
@@ -109,7 +67,7 @@ const evaluteContinuationExpression = (
   expr: ContinuationExpression,
   env: Environment,
   logger: TracingLogger,
-): DenotableValue => {
+): Denotable => {
   if ('primitiveOperation' in expr) {
     logger.debug('Evaluating primitive operation');
     return evaluatePrimitiveOperation(
@@ -146,7 +104,7 @@ const evaluteContinuationExpression = (
 export const evaluate = async (
   ast: Program,
   logger: TracingLogger,
-): Promise<DenotableValue> => {
+): Promise<Denotable> => {
   const environment = new Environment();
 
   return ast.reduce((_, continuation, i) => {

src/utils/exception.ts

@@ -6,4 +6,4 @@ export class InvalidStateError extends Error {}
 
 export class BadArgumentError extends Error {}
 
-export class TypeError extends Error {}
+export class InvalidType extends Error {}

test/interpreter.spec.ts

@@ -10,3 +10,19 @@ test('Add (1 real) and (3 int) => (4 real)', async () => {
   const result = await evaluate(ast, testingLogger);
   expect(result).toEqual({ type: 'real', value: 4 });
 });
+
+/*
+test('String equality', async () => {
+  const ast = peggyParse(await TestPrograms.StringEquality);
+
+  const result = await evaluate(ast, testingLogger);
+  expect(result).toEqual({ type: 'int', value: 1 });
+});
+
+test('String inequality', async () => {
+  const ast = peggyParse(await TestPrograms.StringInEquality);
+
+  const result = await evaluate(ast, testingLogger);
+  expect(result).toEqual({ type: 'int', value: 0 });
+});
+*/

test/programs/index.ts

@@ -4,4 +4,10 @@ export namespace TestPrograms {
   export const AddOneThree = Bun.file(
     join(import.meta.dir + '/add-1-3.cps'),
   ).text();
+  export const StringEquality = Bun.file(
+    join(import.meta.dir + '/string-equal.cps'),
+  ).text();
+  export const StringInEquality = Bun.file(
+    join(import.meta.dir + '/string-unequal.cps'),
+  ).text();
 }

test/programs/string-equal.cps

@@ -0,0 +1 @@
+PRIMOP(==, ["asdf", "asdf"], [result], [])

test/programs/string-unequal.cps

@@ -0,0 +1 @@
+PRIMOP(==, ["asdfasdf", "asdf"], [result], [])

test/signature_match.spec.ts

@@ -0,0 +1,41 @@
+import { expect, test } from 'bun:test';
+import { TestPrograms } from './programs';
+import { peggyParse } from '@/parser';
+import {
+  evaluate,
+  type DenotableFunctionSignature,
+  matchSignature,
+} from '@/interpreter';
+import { testingLogger } from './logger';
+
+test('matches simple signatures', async () => {
+  const simpleSignature: DenotableFunctionSignature[] = [
+    {
+      arguments: ['int'],
+      return: 'int',
+    },
+  ];
+
+  expect(matchSignature(['int'], simpleSignature)).toEqual(simpleSignature[0]);
+});
+
+test('finds first match', async () => {
+  const simpleSignature: DenotableFunctionSignature[] = [
+    {
+      arguments: ['int', 'int'],
+      return: 'int',
+    },
+    {
+      arguments: [['int', 'real'], 'int'],
+      return: 'real',
+    },
+  ];
+
+  expect(matchSignature(['int', 'int'], simpleSignature)).toEqual(
+    simpleSignature[0],
+  );
+
+  expect(matchSignature(['real', 'int'], simpleSignature)).toEqual(
+    simpleSignature[1],
+  );
+});