diff options
Diffstat (limited to 'core/src/main/java/coffee/liz/lambda')
15 files changed, 499 insertions, 499 deletions
diff --git a/core/src/main/java/coffee/liz/lambda/LambdaDriver.java b/core/src/main/java/coffee/liz/lambda/LambdaDriver.java index 2ba8c70..59cee25 100644 --- a/core/src/main/java/coffee/liz/lambda/LambdaDriver.java +++ b/core/src/main/java/coffee/liz/lambda/LambdaDriver.java @@ -20,60 +20,60 @@ import java.util.List; */ public class LambdaDriver { - /** - * Parses source code into an AST. - * - * @param sourceCode - * the source code (either Lambda or Arrow syntax) - * @return the parsed program - */ - public static LambdaProgram parse(final SourceCode sourceCode) { - return switch (sourceCode) { - case SourceCode.Lambda(String source) -> parseLambda(source); - case SourceCode.Arrow(String source) -> parseArrow(source); - }; - } + /** + * Parses source code into an AST. + * + * @param sourceCode + * the source code (either Lambda or Arrow syntax) + * @return the parsed program + */ + public static LambdaProgram parse(final SourceCode sourceCode) { + return switch (sourceCode) { + case SourceCode.Lambda(String source) -> parseLambda(source); + case SourceCode.Arrow(String source) -> parseArrow(source); + }; + } - private static LambdaProgram parseLambda(final String source) { - try (final StringReader reader = new StringReader(source)) { - return new LambdaParser(reader).Program(); - } catch (final ParseException parseException) { - throw new RuntimeException("Failed to parse program", parseException); - } - } + private static LambdaProgram parseLambda(final String source) { + try (final StringReader reader = new StringReader(source)) { + return new LambdaParser(reader).Program(); + } catch (final ParseException parseException) { + throw new RuntimeException("Failed to parse program", parseException); + } + } - private static LambdaProgram parseArrow(final String source) { - try (final StringReader reader = new StringReader(source)) { - return new ArrowParser(reader).Program(); - } catch (final ParseException parseException) { - throw new RuntimeException("Failed to parse program", parseException); - } - } + private static LambdaProgram parseArrow(final String source) { + try (final StringReader reader = new StringReader(source)) { + return new ArrowParser(reader).Program(); + } catch (final ParseException parseException) { + throw new RuntimeException("Failed to parse program", parseException); + } + } - /** - * Parses and evaluates lambda calculus programs. - * - * @param sourceCode - * the source code - * @return the evaluated result - */ - public static Value interpret(final SourceCode sourceCode) { - return interpret(sourceCode, List.of()); - } + /** + * Parses and evaluates lambda calculus programs. + * + * @param sourceCode + * the source code + * @return the evaluated result + */ + public static Value interpret(final SourceCode sourceCode) { + return interpret(sourceCode, List.of()); + } - /** - * Parses and evaluates lambda calculus programs with "FFI"'s. - * - * @param sourceCode - * the source code - * @param bindings - * external Java functions available during evaluation - * @return the evaluated result - */ - public static Value interpret(final SourceCode sourceCode, final List<ExternalBinding> bindings) { - final LambdaProgram program = parse(sourceCode); - final Expression expression = program.expression(); - final List<Macro> macros = program.macros(); - return NormalOrderEvaluator.evaluate(expression, Environment.from(macros, bindings)); - } + /** + * Parses and evaluates lambda calculus programs with "FFI"'s. + * + * @param sourceCode + * the source code + * @param bindings + * external Java functions available during evaluation + * @return the evaluated result + */ + public static Value interpret(final SourceCode sourceCode, final List<ExternalBinding> bindings) { + final LambdaProgram program = parse(sourceCode); + final Expression expression = program.expression(); + final List<Macro> macros = program.macros(); + return NormalOrderEvaluator.evaluate(expression, Environment.from(macros, bindings)); + } } diff --git a/core/src/main/java/coffee/liz/lambda/ast/Expression.java b/core/src/main/java/coffee/liz/lambda/ast/Expression.java index 6d75a08..c2bdd39 100644 --- a/core/src/main/java/coffee/liz/lambda/ast/Expression.java +++ b/core/src/main/java/coffee/liz/lambda/ast/Expression.java @@ -8,21 +8,21 @@ import java.util.Optional; * Represents an expression in the untyped lambda calculus. */ public sealed interface Expression - permits Expression.AbstractionExpression, Expression.IdentifierExpression, Expression.ApplicationExpression { + permits Expression.AbstractionExpression, Expression.IdentifierExpression, Expression.ApplicationExpression { - Optional<SourceComment> comment(); + Optional<SourceComment> comment(); - SourceSpan span(); + SourceSpan span(); - record AbstractionExpression(@NonNull Optional<SourceComment> comment, @NonNull SourceSpan span, - @NonNull String parameter, @NonNull Expression body) implements Expression { - } + record AbstractionExpression(@NonNull Optional<SourceComment> comment, @NonNull SourceSpan span, + @NonNull String parameter, @NonNull Expression body) implements Expression { + } - record ApplicationExpression(@NonNull Optional<SourceComment> comment, @NonNull SourceSpan span, - @NonNull Expression applicable, @NonNull Expression argument) implements Expression { - } + record ApplicationExpression(@NonNull Optional<SourceComment> comment, @NonNull SourceSpan span, + @NonNull Expression applicable, @NonNull Expression argument) implements Expression { + } - record IdentifierExpression(@NonNull Optional<SourceComment> comment, @NonNull SourceSpan span, - @NonNull String name) implements Expression { - } + record IdentifierExpression(@NonNull Optional<SourceComment> comment, @NonNull SourceSpan span, + @NonNull String name) implements Expression { + } } diff --git a/core/src/main/java/coffee/liz/lambda/ast/Macro.java b/core/src/main/java/coffee/liz/lambda/ast/Macro.java index 07ba911..4a485fc 100644 --- a/core/src/main/java/coffee/liz/lambda/ast/Macro.java +++ b/core/src/main/java/coffee/liz/lambda/ast/Macro.java @@ -8,5 +8,5 @@ import java.util.Optional; * A named macro definition that maps an identifier to an expression. */ public record Macro(@NonNull Optional<SourceComment> comment, @NonNull SourceSpan span, @NonNull String name, - @NonNull Expression expression) { + @NonNull Expression expression) { } diff --git a/core/src/main/java/coffee/liz/lambda/ast/SourceCode.java b/core/src/main/java/coffee/liz/lambda/ast/SourceCode.java index 200c45e..c2112ad 100644 --- a/core/src/main/java/coffee/liz/lambda/ast/SourceCode.java +++ b/core/src/main/java/coffee/liz/lambda/ast/SourceCode.java @@ -4,24 +4,24 @@ package coffee.liz.lambda.ast; * Represents source code in one of the supported lambda calculus syntaxes. */ public sealed interface SourceCode { - static SourceCode ofLambda(final String source) { - return new Lambda(source); - } + static SourceCode ofLambda(final String source) { + return new Lambda(source); + } - static SourceCode ofArrow(final String source) { - return new Arrow(source); - } + static SourceCode ofArrow(final String source) { + return new Arrow(source); + } - record Lambda(String source) implements SourceCode { - } + record Lambda(String source) implements SourceCode { + } - record Arrow(String source) implements SourceCode { - } + record Arrow(String source) implements SourceCode { + } - /** - * Supported syntax types for {@link SourceCode}. - */ - enum Syntax { - LAMBDA, ARROW - } + /** + * Supported syntax types for {@link SourceCode}. + */ + enum Syntax { + LAMBDA, ARROW + } } diff --git a/core/src/main/java/coffee/liz/lambda/ast/SourceComment.java b/core/src/main/java/coffee/liz/lambda/ast/SourceComment.java index da6b5ab..8e50f5f 100644 --- a/core/src/main/java/coffee/liz/lambda/ast/SourceComment.java +++ b/core/src/main/java/coffee/liz/lambda/ast/SourceComment.java @@ -12,10 +12,10 @@ import lombok.NonNull; */ public record SourceComment(@NonNull String text, @NonNull SourceSpan span) { - /** - * Returns true if this comment is on the same line as the given span's end. - */ - public boolean isInlineAfter(final SourceSpan previous) { - return previous != null && previous.endLine() == this.span.startLine(); - } + /** + * Returns true if this comment is on the same line as the given span's end. + */ + public boolean isInlineAfter(final SourceSpan previous) { + return previous != null && previous.endLine() == this.span.startLine(); + } } diff --git a/core/src/main/java/coffee/liz/lambda/ast/SourceSpan.java b/core/src/main/java/coffee/liz/lambda/ast/SourceSpan.java index 7df9bcd..80e06f9 100644 --- a/core/src/main/java/coffee/liz/lambda/ast/SourceSpan.java +++ b/core/src/main/java/coffee/liz/lambda/ast/SourceSpan.java @@ -13,12 +13,12 @@ package coffee.liz.lambda.ast; * 1-based column number where the span ends */ public record SourceSpan(int startLine, int startColumn, int endLine, int endColumn) { - public static final SourceSpan UNKNOWN = new SourceSpan(0, 0, 0, 0); + public static final SourceSpan UNKNOWN = new SourceSpan(0, 0, 0, 0); - /** - * Returns true if this span ends on the same line that the other span starts. - */ - public boolean isOnSameLine(final SourceSpan other) { - return this.endLine == other.startLine; - } + /** + * Returns true if this span ends on the same line that the other span starts. + */ + public boolean isOnSameLine(final SourceSpan other) { + return this.endLine == other.startLine; + } } diff --git a/core/src/main/java/coffee/liz/lambda/bind/ExternalBinding.java b/core/src/main/java/coffee/liz/lambda/bind/ExternalBinding.java index 4895972..7a8ae40 100644 --- a/core/src/main/java/coffee/liz/lambda/bind/ExternalBinding.java +++ b/core/src/main/java/coffee/liz/lambda/bind/ExternalBinding.java @@ -14,10 +14,10 @@ import java.util.function.BiFunction; */ public interface ExternalBinding extends BiFunction<Environment, Value, Value> { - /** - * Returns the name used to reference this binding in environment. - * - * @return the binding name - */ - String getName(); + /** + * Returns the name used to reference this binding in environment. + * + * @return the binding name + */ + String getName(); } diff --git a/core/src/main/java/coffee/liz/lambda/bind/Tick.java b/core/src/main/java/coffee/liz/lambda/bind/Tick.java index 0fa4de5..c4ad8ee 100644 --- a/core/src/main/java/coffee/liz/lambda/bind/Tick.java +++ b/core/src/main/java/coffee/liz/lambda/bind/Tick.java @@ -11,12 +11,12 @@ import java.util.concurrent.atomic.AtomicInteger; */ @Getter public class Tick implements ExternalBinding { - private final String name = "Tick"; - private final AtomicInteger counter = new AtomicInteger(0); + private final String name = "Tick"; + private final AtomicInteger counter = new AtomicInteger(0); - @Override - public Value apply(final Environment environment, final Value value) { - counter.incrementAndGet(); - return value; - } + @Override + public Value apply(final Environment environment, final Value value) { + counter.incrementAndGet(); + return value; + } } diff --git a/core/src/main/java/coffee/liz/lambda/bind/ToChurch.java b/core/src/main/java/coffee/liz/lambda/bind/ToChurch.java index bfddd86..315622a 100644 --- a/core/src/main/java/coffee/liz/lambda/bind/ToChurch.java +++ b/core/src/main/java/coffee/liz/lambda/bind/ToChurch.java @@ -22,28 +22,28 @@ import lombok.Getter; */ @Getter public class ToChurch implements ExternalBinding { - private final String name = "ToChurch"; + private final String name = "ToChurch"; - /** - * Converts a free variable containing an integer string to a Church numeral. - * - * @param env - * the current environment - * @param val - * a Free value whose name is an integer string - * @return a Closure representing the Church numeral - */ - @Override - public Value apply(final Environment env, final Value val) { - final Free free = (Free) val; - final int n = Integer.parseInt(free.name()); + /** + * Converts a free variable containing an integer string to a Church numeral. + * + * @param env + * the current environment + * @param val + * a Free value whose name is an integer string + * @return a Closure representing the Church numeral + */ + @Override + public Value apply(final Environment env, final Value val) { + final Free free = (Free) val; + final int n = Integer.parseInt(free.name()); - Expression body = new IdentifierExpression(Optional.empty(), SourceSpan.UNKNOWN, "x"); - for (int i = 0; i < n; i++) { - body = new ApplicationExpression(Optional.empty(), SourceSpan.UNKNOWN, - new IdentifierExpression(Optional.empty(), SourceSpan.UNKNOWN, "f"), body); - } + Expression body = new IdentifierExpression(Optional.empty(), SourceSpan.UNKNOWN, "x"); + for (int i = 0; i < n; i++) { + body = new ApplicationExpression(Optional.empty(), SourceSpan.UNKNOWN, + new IdentifierExpression(Optional.empty(), SourceSpan.UNKNOWN, "f"), body); + } - return new Closure(env, "f", new AbstractionExpression(Optional.empty(), SourceSpan.UNKNOWN, "x", body)); - } + return new Closure(env, "f", new AbstractionExpression(Optional.empty(), SourceSpan.UNKNOWN, "x", body)); + } } diff --git a/core/src/main/java/coffee/liz/lambda/eval/Environment.java b/core/src/main/java/coffee/liz/lambda/eval/Environment.java index 8854719..a4ec24a 100644 --- a/core/src/main/java/coffee/liz/lambda/eval/Environment.java +++ b/core/src/main/java/coffee/liz/lambda/eval/Environment.java @@ -18,92 +18,92 @@ import java.util.stream.Collectors; */ @RequiredArgsConstructor public final class Environment { - /** Named expansions */ - private final Map<String, Expression> macros; + /** Named expansions */ + private final Map<String, Expression> macros; - /** "FFI" */ - private final Map<String, ExternalBinding> externalBindings; + /** "FFI" */ + private final Map<String, ExternalBinding> externalBindings; - /** Variable name bound at this scope level. Null for root. */ - @Nullable - private final String boundName; + /** Variable name bound at this scope level. Null for root. */ + @Nullable + private final String boundName; - /** Lazily-evaluated value for boundName, or null for root. */ - @Nullable - private final Supplier<Value> boundValue; + /** Lazily-evaluated value for boundName, or null for root. */ + @Nullable + private final Supplier<Value> boundValue; - /** Enclosing scope, or null for root. Forms a linked list of bindings. */ - @Nullable - private final Environment parent; + /** Enclosing scope, or null for root. Forms a linked list of bindings. */ + @Nullable + private final Environment parent; - /** - * Creates an environment from macro and external binding lists. - * - * @param macros - * program macro definitions - * @param externalBindings - * external Java bindings for FFI - * @return the new environment - */ - public static Environment from(final List<Macro> macros, final List<ExternalBinding> externalBindings) { - return new Environment(macros.stream().collect(Collectors.toMap(Macro::name, Macro::expression)), - externalBindings.stream().collect(Collectors.toMap(ExternalBinding::getName, Function.identity())), - null, null, null); - } + /** + * Creates an environment from macro and external binding lists. + * + * @param macros + * program macro definitions + * @param externalBindings + * external Java bindings for FFI + * @return the new environment + */ + public static Environment from(final List<Macro> macros, final List<ExternalBinding> externalBindings) { + return new Environment(macros.stream().collect(Collectors.toMap(Macro::name, Macro::expression)), + externalBindings.stream().collect(Collectors.toMap(ExternalBinding::getName, Function.identity())), + null, null, null); + } - /** - * Creates a child scope. - * - * @param name - * the variable name - * @param value - * the value supplier (thunk) - * @return a new environment with the binding added - */ - public Environment extend(final String name, final Supplier<Value> value) { - return new Environment(macros, externalBindings, name, value, this); - } + /** + * Creates a child scope. + * + * @param name + * the variable name + * @param value + * the value supplier (thunk) + * @return a new environment with the binding added + */ + public Environment extend(final String name, final Supplier<Value> value) { + return new Environment(macros, externalBindings, name, value, this); + } - /** - * Looks up a name, checking bindings, then macros, then external bindings. - * - * @param name - * the name to look up - * @return the lookup result, or empty if not found - */ - public Optional<LookupResult> lookup(final String name) { - for (Environment env = this; env != null; env = env.parent) { - if (!name.equals(env.boundName)) { - continue; - } - return Optional.of(new LookupResult.Binding(env.boundValue)); - } + /** + * Looks up a name, checking bindings, then macros, then external bindings. + * + * @param name + * the name to look up + * @return the lookup result, or empty if not found + */ + public Optional<LookupResult> lookup(final String name) { + for (Environment env = this; env != null; env = env.parent) { + if (!name.equals(env.boundName)) { + continue; + } + return Optional.of(new LookupResult.Binding(env.boundValue)); + } - final Expression macro = macros.get(name); - if (macro != null) { - return Optional.of(new LookupResult.Macro(macro)); - } + final Expression macro = macros.get(name); + if (macro != null) { + return Optional.of(new LookupResult.Macro(macro)); + } - final ExternalBinding external = externalBindings.get(name); - if (external != null) { - return Optional.of(new LookupResult.External(external)); - } + final ExternalBinding external = externalBindings.get(name); + if (external != null) { + return Optional.of(new LookupResult.External(external)); + } - return Optional.empty(); - } + return Optional.empty(); + } - /** - * Result of looking up a name in the environment. - */ - public sealed interface LookupResult { - /** A local variable binding. */ - record Binding(Supplier<Value> value) implements LookupResult { - } - /** A macro definition. */ - record Macro(Expression expression) implements LookupResult { - } - /** An external Java binding. */ - record External(ExternalBinding binding) implements LookupResult { - } - } + /** + * Result of looking up a name in the environment. + */ + public sealed interface LookupResult { + /** A local variable binding. */ + record Binding(Supplier<Value> value) implements LookupResult { + } + /** A macro definition. */ + record Macro(Expression expression) implements LookupResult { + } + /** An external Java binding. */ + record External(ExternalBinding binding) implements LookupResult { + } + } } diff --git a/core/src/main/java/coffee/liz/lambda/eval/EvaluationDepthExceededException.java b/core/src/main/java/coffee/liz/lambda/eval/EvaluationDepthExceededException.java index 7926004..8f2ad2e 100644 --- a/core/src/main/java/coffee/liz/lambda/eval/EvaluationDepthExceededException.java +++ b/core/src/main/java/coffee/liz/lambda/eval/EvaluationDepthExceededException.java @@ -7,10 +7,10 @@ import lombok.Getter; */ @Getter public final class EvaluationDepthExceededException extends RuntimeException { - private final int maxDepth; + private final int maxDepth; - public EvaluationDepthExceededException(final int maxDepth) { - super("Evaluation exceeded maximum depth of " + maxDepth); - this.maxDepth = maxDepth; - } + public EvaluationDepthExceededException(final int maxDepth) { + super("Evaluation exceeded maximum depth of " + maxDepth); + this.maxDepth = maxDepth; + } } diff --git a/core/src/main/java/coffee/liz/lambda/eval/NormalOrderEvaluator.java b/core/src/main/java/coffee/liz/lambda/eval/NormalOrderEvaluator.java index 28eb69b..d9bcba3 100644 --- a/core/src/main/java/coffee/liz/lambda/eval/NormalOrderEvaluator.java +++ b/core/src/main/java/coffee/liz/lambda/eval/NormalOrderEvaluator.java @@ -18,84 +18,84 @@ import coffee.liz.lambda.eval.Value.Free; */ public final class NormalOrderEvaluator { - public static final int DEFAULT_MAX_DEPTH = 140; + public static final int DEFAULT_MAX_DEPTH = 140; - /** - * Evaluates an expression in the given environment with default depth limit. - * - * @param term - * the expression to evaluate - * @param env - * the environment containing bindings - * @return the resulting value - * @throws EvaluationDepthExceededException - * if evaluation exceeds {@link #DEFAULT_MAX_DEPTH} - */ - public static Value evaluate(final Expression term, final Environment env) { - return evaluate(term, env, DEFAULT_MAX_DEPTH); - } + /** + * Evaluates an expression in the given environment with default depth limit. + * + * @param term + * the expression to evaluate + * @param env + * the environment containing bindings + * @return the resulting value + * @throws EvaluationDepthExceededException + * if evaluation exceeds {@link #DEFAULT_MAX_DEPTH} + */ + public static Value evaluate(final Expression term, final Environment env) { + return evaluate(term, env, DEFAULT_MAX_DEPTH); + } - /** - * Evaluates an expression in the given environment with specified depth limit. - * - * @param term - * the expression to evaluate - * @param env - * the environment containing bindings - * @param maxDepth - * maximum evaluation depth - * @return the resulting value - * @throws EvaluationDepthExceededException - * if evaluation exceeds maxDepth - */ - public static Value evaluate(final Expression term, final Environment env, final int maxDepth) { - return evaluate(term, env, maxDepth, 0); - } + /** + * Evaluates an expression in the given environment with specified depth limit. + * + * @param term + * the expression to evaluate + * @param env + * the environment containing bindings + * @param maxDepth + * maximum evaluation depth + * @return the resulting value + * @throws EvaluationDepthExceededException + * if evaluation exceeds maxDepth + */ + public static Value evaluate(final Expression term, final Environment env, final int maxDepth) { + return evaluate(term, env, maxDepth, 0); + } - private static Value evaluate(final Expression term, final Environment env, final int maxDepth, final int depth) { - if (depth > maxDepth) { - throw new EvaluationDepthExceededException(maxDepth); - } + private static Value evaluate(final Expression term, final Environment env, final int maxDepth, final int depth) { + if (depth > maxDepth) { + throw new EvaluationDepthExceededException(maxDepth); + } - return switch (term) { - case IdentifierExpression(var _, var _, final String name) -> - env.lookup(name).map(result -> switch (result) { - case LookupResult.Binding(final var value) -> value.get(); - case LookupResult.Macro(final var expr) -> evaluate(expr, env, maxDepth, depth + 1); - case LookupResult.External(final var binding) -> new Free(binding.getName()); - }).orElseGet(() -> new Free(name)); + return switch (term) { + case IdentifierExpression(var _, var _, final String name) -> + env.lookup(name).map(result -> switch (result) { + case LookupResult.Binding(final var value) -> value.get(); + case LookupResult.Macro(final var expr) -> evaluate(expr, env, maxDepth, depth + 1); + case LookupResult.External(final var binding) -> new Free(binding.getName()); + }).orElseGet(() -> new Free(name)); - case AbstractionExpression(var _, var _, final String parameter, final Expression body) -> - new Closure(env, parameter, body); + case AbstractionExpression(var _, var _, final String parameter, final Expression body) -> + new Closure(env, parameter, body); - case ApplicationExpression(var _, var _, final Expression func, final Expression arg) -> - apply(evaluate(func, env, maxDepth, depth + 1), arg, env, maxDepth, depth + 1); - }; - } + case ApplicationExpression(var _, var _, final Expression func, final Expression arg) -> + apply(evaluate(func, env, maxDepth, depth + 1), arg, env, maxDepth, depth + 1); + }; + } - private static Value apply(final Value funcVal, final Expression arg, final Environment argEnv, final int maxDepth, - final int depth) { - if (depth > maxDepth) { - throw new EvaluationDepthExceededException(maxDepth); - } + private static Value apply(final Value funcVal, final Expression arg, final Environment argEnv, final int maxDepth, + final int depth) { + if (depth > maxDepth) { + throw new EvaluationDepthExceededException(maxDepth); + } - return switch (funcVal) { - case Closure(final Environment closureEnv, final String parameter, final Expression body) -> { - final Thunk<Value> thunk = new Thunk<>(() -> evaluate(arg, argEnv, maxDepth, depth + 1)); - final Environment newEnv = closureEnv.extend(parameter, thunk); - yield evaluate(body, newEnv, maxDepth, depth + 1); - } + return switch (funcVal) { + case Closure(final Environment closureEnv, final String parameter, final Expression body) -> { + final Thunk<Value> thunk = new Thunk<>(() -> evaluate(arg, argEnv, maxDepth, depth + 1)); + final Environment newEnv = closureEnv.extend(parameter, thunk); + yield evaluate(body, newEnv, maxDepth, depth + 1); + } - case Free(final String name) -> - argEnv.lookup(name).filter(r -> r instanceof LookupResult.External).map(r -> { - final ExternalBinding binding = ((LookupResult.External) r).binding(); - return binding.apply(argEnv, evaluate(arg, argEnv, maxDepth, depth + 1)); - }).orElseGet(() -> new Application(funcVal, evaluate(arg, argEnv, maxDepth, depth + 1))); + case Free(final String name) -> + argEnv.lookup(name).filter(r -> r instanceof LookupResult.External).map(r -> { + final ExternalBinding binding = ((LookupResult.External) r).binding(); + return binding.apply(argEnv, evaluate(arg, argEnv, maxDepth, depth + 1)); + }).orElseGet(() -> new Application(funcVal, evaluate(arg, argEnv, maxDepth, depth + 1))); - case Application app -> { - final Value argVal = evaluate(arg, argEnv, maxDepth, depth + 1); - yield new Application(app, argVal); - } - }; - } + case Application app -> { + final Value argVal = evaluate(arg, argEnv, maxDepth, depth + 1); + yield new Application(app, argVal); + } + }; + } } diff --git a/core/src/main/java/coffee/liz/lambda/eval/Thunk.java b/core/src/main/java/coffee/liz/lambda/eval/Thunk.java index 07c89bf..fdbda93 100644 --- a/core/src/main/java/coffee/liz/lambda/eval/Thunk.java +++ b/core/src/main/java/coffee/liz/lambda/eval/Thunk.java @@ -12,16 +12,16 @@ import java.util.function.Supplier; */ @RequiredArgsConstructor public final class Thunk<T> implements Supplier<T> { - private final Supplier<T> thinker; // https://www.youtube.com/shorts/Dzksib8YxSY - private T cached = null; - private boolean evaluated = false; + private final Supplier<T> thinker; // https://www.youtube.com/shorts/Dzksib8YxSY + private T cached = null; + private boolean evaluated = false; - @Override - public T get() { - if (!evaluated) { - cached = thinker.get(); - evaluated = true; - } - return cached; - } + @Override + public T get() { + if (!evaluated) { + cached = thinker.get(); + evaluated = true; + } + return cached; + } }
\ No newline at end of file diff --git a/core/src/main/java/coffee/liz/lambda/eval/Value.java b/core/src/main/java/coffee/liz/lambda/eval/Value.java index 58b9ba4..dc459ff 100644 --- a/core/src/main/java/coffee/liz/lambda/eval/Value.java +++ b/core/src/main/java/coffee/liz/lambda/eval/Value.java @@ -7,36 +7,36 @@ import coffee.liz.lambda.ast.Expression; */ public sealed interface Value permits Value.Closure, Value.Application, Value.Free { - /** - * A closure capturing an environment, parameter, and body. - * - * @param env - * the captured environment - * @param parameter - * the bound parameter name - * @param body - * the lambda body expression - */ - record Closure(Environment env, String parameter, Expression body) implements Value { - } + /** + * A closure capturing an environment, parameter, and body. + * + * @param env + * the captured environment + * @param parameter + * the bound parameter name + * @param body + * the lambda body expression + */ + record Closure(Environment env, String parameter, Expression body) implements Value { + } - /** - * A symbolic application of a function to an argument. - * - * @param function - * the function - * @param argument - * the argument - */ - record Application(Value function, Value argument) implements Value { - } + /** + * A symbolic application of a function to an argument. + * + * @param function + * the function + * @param argument + * the argument + */ + record Application(Value function, Value argument) implements Value { + } - /** - * A free variable. - * - * @param name - * the variable name - */ - record Free(String name) implements Value { - } + /** + * A free variable. + * + * @param name + * the variable name + */ + record Free(String name) implements Value { + } } diff --git a/core/src/main/java/coffee/liz/lambda/format/Formatter.java b/core/src/main/java/coffee/liz/lambda/format/Formatter.java index 1ac3e95..e4fbc0c 100644 --- a/core/src/main/java/coffee/liz/lambda/format/Formatter.java +++ b/core/src/main/java/coffee/liz/lambda/format/Formatter.java @@ -21,218 +21,218 @@ import java.util.Optional; @RequiredArgsConstructor public final class Formatter { - private final Syntax syntax; + private final Syntax syntax; - public String format(final LambdaProgram program) { - final StringBuilder sb = new StringBuilder(); - SourceSpan previousEnd = null; + public String format(final LambdaProgram program) { + final StringBuilder sb = new StringBuilder(); + SourceSpan previousEnd = null; - for (int i = 0; i < program.macros().size(); i++) { - final Macro macro = program.macros().get(i); + for (int i = 0; i < program.macros().size(); i++) { + final Macro macro = program.macros().get(i); - if (macro.comment().isPresent()) { - final SourceComment comment = macro.comment().get(); - final String leadingPart = getLeadingCommentPart(comment, previousEnd); - if (!leadingPart.isEmpty()) { - sb.append(leadingPart); - if (!leadingPart.endsWith("\n")) { - sb.append("\n"); - } - } - } + if (macro.comment().isPresent()) { + final SourceComment comment = macro.comment().get(); + final String leadingPart = getLeadingCommentPart(comment, previousEnd); + if (!leadingPart.isEmpty()) { + sb.append(leadingPart); + if (!leadingPart.endsWith("\n")) { + sb.append("\n"); + } + } + } - sb.append("let ").append(macro.name()).append(" = "); - sb.append(formatExpression(macro.expression(), false)); - sb.append(";"); + sb.append("let ").append(macro.name()).append(" = "); + sb.append(formatExpression(macro.expression(), false)); + sb.append(";"); - final Optional<String> inlineComment = getInlineCommentAfter(macro.span(), program, i); - inlineComment.ifPresent(c -> sb.append(" ").append(c)); - sb.append("\n"); + final Optional<String> inlineComment = getInlineCommentAfter(macro.span(), program, i); + inlineComment.ifPresent(c -> sb.append(" ").append(c)); + sb.append("\n"); - previousEnd = macro.span(); - } + previousEnd = macro.span(); + } - boolean isTrailingComment = false; - boolean inlinePartAlreadyOutput = false; + boolean isTrailingComment = false; + boolean inlinePartAlreadyOutput = false; - if (program.expression().comment().isPresent()) { - final SourceComment comment = program.expression().comment().get(); + if (program.expression().comment().isPresent()) { + final SourceComment comment = program.expression().comment().get(); - isTrailingComment = comment.span().startLine() >= program.expression().span().startLine() - && comment.span().startColumn() > program.expression().span().startColumn(); + isTrailingComment = comment.span().startLine() >= program.expression().span().startLine() + && comment.span().startColumn() > program.expression().span().startColumn(); - if (!isTrailingComment) { - inlinePartAlreadyOutput = previousEnd != null && comment.isInlineAfter(previousEnd); + if (!isTrailingComment) { + inlinePartAlreadyOutput = previousEnd != null && comment.isInlineAfter(previousEnd); - final String leadingPart = getLeadingCommentPart(comment, previousEnd); - if (!leadingPart.isEmpty()) { - sb.append(leadingPart); - if (!leadingPart.endsWith("\n")) { - sb.append("\n"); - } - } else if (!program.macros().isEmpty()) { - sb.append("\n"); - } - } else if (!program.macros().isEmpty()) { - sb.append("\n"); - } - } else if (!program.macros().isEmpty()) { - sb.append("\n"); - } + final String leadingPart = getLeadingCommentPart(comment, previousEnd); + if (!leadingPart.isEmpty()) { + sb.append(leadingPart); + if (!leadingPart.endsWith("\n")) { + sb.append("\n"); + } + } else if (!program.macros().isEmpty()) { + sb.append("\n"); + } + } else if (!program.macros().isEmpty()) { + sb.append("\n"); + } + } else if (!program.macros().isEmpty()) { + sb.append("\n"); + } - sb.append(formatExpression(program.expression(), false)); + sb.append(formatExpression(program.expression(), false)); - if (program.expression().comment().isPresent() && !inlinePartAlreadyOutput && isTrailingComment) { - sb.append(" ").append(program.expression().comment().get().text()); - } + if (program.expression().comment().isPresent() && !inlinePartAlreadyOutput && isTrailingComment) { + sb.append(" ").append(program.expression().comment().get().text()); + } - return sb.toString(); - } + return sb.toString(); + } - /** - * Gets the inline portion of a comment (first line if on same line as previous - * element). - */ - private String getInlineCommentPart(final SourceComment comment, final SourceSpan previousEnd) { - if (previousEnd == null || !comment.isInlineAfter(previousEnd)) { - return ""; - } - final String text = comment.text(); - final int newlineIndex = text.indexOf('\n'); - return newlineIndex == -1 ? text : text.substring(0, newlineIndex); - } + /** + * Gets the inline portion of a comment (first line if on same line as previous + * element). + */ + private String getInlineCommentPart(final SourceComment comment, final SourceSpan previousEnd) { + if (previousEnd == null || !comment.isInlineAfter(previousEnd)) { + return ""; + } + final String text = comment.text(); + final int newlineIndex = text.indexOf('\n'); + return newlineIndex == -1 ? text : text.substring(0, newlineIndex); + } - /** - * Gets the leading portion of a comment (all lines except inline first line). - */ - private String getLeadingCommentPart(final SourceComment comment, final SourceSpan previousEnd) { - if (previousEnd == null || !comment.isInlineAfter(previousEnd)) { - return comment.text(); - } - final String text = comment.text(); - final int newlineIndex = text.indexOf('\n'); - return newlineIndex == -1 ? "" : text.substring(newlineIndex + 1); - } + /** + * Gets the leading portion of a comment (all lines except inline first line). + */ + private String getLeadingCommentPart(final SourceComment comment, final SourceSpan previousEnd) { + if (previousEnd == null || !comment.isInlineAfter(previousEnd)) { + return comment.text(); + } + final String text = comment.text(); + final int newlineIndex = text.indexOf('\n'); + return newlineIndex == -1 ? "" : text.substring(newlineIndex + 1); + } - /** - * Gets the inline comment that appears after the given span, if any. - */ - private Optional<String> getInlineCommentAfter(final SourceSpan span, final LambdaProgram program, - final int macroIndex) { - if (macroIndex + 1 < program.macros().size()) { - final Macro nextMacro = program.macros().get(macroIndex + 1); - if (nextMacro.comment().isPresent() && nextMacro.comment().get().isInlineAfter(span)) { - final String inlinePart = getInlineCommentPart(nextMacro.comment().get(), span); - if (!inlinePart.isEmpty()) { - return Optional.of(inlinePart); - } - } - } - if (macroIndex == program.macros().size() - 1 && program.expression().comment().isPresent() - && program.expression().comment().get().isInlineAfter(span)) { - final String inlinePart = getInlineCommentPart(program.expression().comment().get(), span); - if (!inlinePart.isEmpty()) { - return Optional.of(inlinePart); - } - } - return Optional.empty(); - } + /** + * Gets the inline comment that appears after the given span, if any. + */ + private Optional<String> getInlineCommentAfter(final SourceSpan span, final LambdaProgram program, + final int macroIndex) { + if (macroIndex + 1 < program.macros().size()) { + final Macro nextMacro = program.macros().get(macroIndex + 1); + if (nextMacro.comment().isPresent() && nextMacro.comment().get().isInlineAfter(span)) { + final String inlinePart = getInlineCommentPart(nextMacro.comment().get(), span); + if (!inlinePart.isEmpty()) { + return Optional.of(inlinePart); + } + } + } + if (macroIndex == program.macros().size() - 1 && program.expression().comment().isPresent() + && program.expression().comment().get().isInlineAfter(span)) { + final String inlinePart = getInlineCommentPart(program.expression().comment().get(), span); + if (!inlinePart.isEmpty()) { + return Optional.of(inlinePart); + } + } + return Optional.empty(); + } - private String formatExpression(final Expression expr, final boolean needsParens) { - return switch (expr) { - case AbstractionExpression abs -> formatAbstraction(abs, needsParens); - case ApplicationExpression app -> formatApplication(app, needsParens); - case IdentifierExpression id -> id.name(); - }; - } + private String formatExpression(final Expression expr, final boolean needsParens) { + return switch (expr) { + case AbstractionExpression abs -> formatAbstraction(abs, needsParens); + case ApplicationExpression app -> formatApplication(app, needsParens); + case IdentifierExpression id -> id.name(); + }; + } - private String formatAbstraction(final AbstractionExpression abs, final boolean needsParens) { - final StringBuilder sb = new StringBuilder(); + private String formatAbstraction(final AbstractionExpression abs, final boolean needsParens) { + final StringBuilder sb = new StringBuilder(); - if (needsParens) { - sb.append("("); - } - switch (syntax) { - case LAMBDA -> { - sb.append("λ").append(abs.parameter()).append("."); - sb.append(formatExpression(abs.body(), false)); - } - case ARROW -> { - sb.append(abs.parameter()).append(" -> "); - sb.append(formatExpression(abs.body(), false)); - } - } - if (needsParens) { - sb.append(")"); - } + if (needsParens) { + sb.append("("); + } + switch (syntax) { + case LAMBDA -> { + sb.append("λ").append(abs.parameter()).append("."); + sb.append(formatExpression(abs.body(), false)); + } + case ARROW -> { + sb.append(abs.parameter()).append(" -> "); + sb.append(formatExpression(abs.body(), false)); + } + } + if (needsParens) { + sb.append(")"); + } - return sb.toString(); - } + return sb.toString(); + } - private String formatApplication(final ApplicationExpression app, final boolean needsParens) { - return switch (syntax) { - case LAMBDA -> formatLambdaApplication(app, needsParens); - case ARROW -> formatArrowApplication(app); - }; - } + private String formatApplication(final ApplicationExpression app, final boolean needsParens) { + return switch (syntax) { + case LAMBDA -> formatLambdaApplication(app, needsParens); + case ARROW -> formatArrowApplication(app); + }; + } - private String formatLambdaApplication(final ApplicationExpression app, final boolean needsParens) { - final StringBuilder sb = new StringBuilder(); + private String formatLambdaApplication(final ApplicationExpression app, final boolean needsParens) { + final StringBuilder sb = new StringBuilder(); - if (needsParens) { - sb.append("("); - } + if (needsParens) { + sb.append("("); + } - final boolean funcNeedsParens = app.applicable() instanceof AbstractionExpression; - sb.append(formatExpression(app.applicable(), funcNeedsParens)); + final boolean funcNeedsParens = app.applicable() instanceof AbstractionExpression; + sb.append(formatExpression(app.applicable(), funcNeedsParens)); - sb.append(" "); + sb.append(" "); - final boolean argNeedsParens = app.argument() instanceof ApplicationExpression - || app.argument() instanceof AbstractionExpression; - sb.append(formatExpression(app.argument(), argNeedsParens)); + final boolean argNeedsParens = app.argument() instanceof ApplicationExpression + || app.argument() instanceof AbstractionExpression; + sb.append(formatExpression(app.argument(), argNeedsParens)); - if (needsParens) { - sb.append(")"); - } + if (needsParens) { + sb.append(")"); + } - return sb.toString(); - } + return sb.toString(); + } - private String formatArrowApplication(final ApplicationExpression app) { - final StringBuilder sb = new StringBuilder(); + private String formatArrowApplication(final ApplicationExpression app) { + final StringBuilder sb = new StringBuilder(); - Expression func = app.applicable(); - final List<Expression> args = new ArrayList<>(); - args.add(app.argument()); + Expression func = app.applicable(); + final List<Expression> args = new ArrayList<>(); + args.add(app.argument()); - while (func instanceof ApplicationExpression appFunc) { - args.addFirst(appFunc.argument()); - func = appFunc.applicable(); - } + while (func instanceof ApplicationExpression appFunc) { + args.addFirst(appFunc.argument()); + func = appFunc.applicable(); + } - final boolean funcNeedsParens = func instanceof AbstractionExpression; - if (funcNeedsParens) { - sb.append("("); - } - sb.append(formatExpression(func, false)); - if (funcNeedsParens) { - sb.append(")"); - } + final boolean funcNeedsParens = func instanceof AbstractionExpression; + if (funcNeedsParens) { + sb.append("("); + } + sb.append(formatExpression(func, false)); + if (funcNeedsParens) { + sb.append(")"); + } - for (final Expression arg : args) { - sb.append("("); - sb.append(formatExpression(arg, false)); - sb.append(")"); - } + for (final Expression arg : args) { + sb.append("("); + sb.append(formatExpression(arg, false)); + sb.append(")"); + } - return sb.toString(); - } + return sb.toString(); + } - /** - * Formats a program in the specified syntax. - */ - public static String emit(final LambdaProgram program, final Syntax syntax) { - return new Formatter(syntax).format(program); - } + /** + * Formats a program in the specified syntax. + */ + public static String emit(final LambdaProgram program, final Syntax syntax) { + return new Formatter(syntax).format(program); + } } |