From b530d6360308ac1f68cf2508fa5bd4a085a8bec0 Mon Sep 17 00:00:00 2001 From: nea Date: Wed, 9 Aug 2023 16:18:48 +0200 Subject: Initial commit --- build.gradle.kts | 5 + gradle/wrapper/gradle-wrapper.jar | Bin 0 -> 61608 bytes gradle/wrapper/gradle-wrapper.properties | 6 + gradlew | 244 +++++++++++++++++++++++++++++++ gradlew.bat | 92 ++++++++++++ src/CoreBindings.kt | 109 ++++++++++++++ src/LispAst.kt | 41 ++++++ src/LispData.kt | 105 +++++++++++++ src/LispErrorReporter.kt | 15 ++ src/LispExecutionContext.kt | 61 ++++++++ src/LispParser.kt | 116 +++++++++++++++ src/LispParsingError.kt | 4 + src/LispPosition.kt | 21 +++ src/StackFrame.kt | 32 ++++ src/StringRacer.kt | 81 ++++++++++ test/res/test.lisp | 11 ++ test/src/TestLisp.kt | 14 ++ 17 files changed, 957 insertions(+) create mode 100644 build.gradle.kts create mode 100644 gradle/wrapper/gradle-wrapper.jar create mode 100644 gradle/wrapper/gradle-wrapper.properties create mode 100755 gradlew create mode 100644 gradlew.bat create mode 100644 src/CoreBindings.kt create mode 100644 src/LispAst.kt create mode 100644 src/LispData.kt create mode 100644 src/LispErrorReporter.kt create mode 100644 src/LispExecutionContext.kt create mode 100644 src/LispParser.kt create mode 100644 src/LispParsingError.kt create mode 100644 src/LispPosition.kt create mode 100644 src/StackFrame.kt create mode 100644 src/StringRacer.kt create mode 100644 test/res/test.lisp create mode 100644 test/src/TestLisp.kt diff --git a/build.gradle.kts b/build.gradle.kts new file mode 100644 index 0000000..0a2df9e --- /dev/null +++ b/build.gradle.kts @@ -0,0 +1,5 @@ +plugins { kotlin("jvm").version("1.7.20"); java; `maven-publish` } +repositories { mavenCentral() } +java.toolchain { languageVersion.set(JavaLanguageVersion.of(8)) } +sourceSets.main { java.setSrcDirs(listOf("src/")); resources.setSrcDirs(listOf("res")) } +sourceSets.test { java.setSrcDirs(listOf("test/src")); resources.setSrcDirs(listOf("test/res")) } diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar new file mode 100644 index 0000000..ccebba7 Binary files /dev/null and b/gradle/wrapper/gradle-wrapper.jar differ diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties new file mode 100644 index 0000000..42defcc --- /dev/null +++ b/gradle/wrapper/gradle-wrapper.properties @@ -0,0 +1,6 @@ +distributionBase=GRADLE_USER_HOME +distributionPath=wrapper/dists +distributionUrl=https\://services.gradle.org/distributions/gradle-8.0-bin.zip +networkTimeout=10000 +zipStoreBase=GRADLE_USER_HOME +zipStorePath=wrapper/dists diff --git a/gradlew b/gradlew new file mode 100755 index 0000000..79a61d4 --- /dev/null +++ b/gradlew @@ -0,0 +1,244 @@ +#!/bin/sh + +# +# Copyright © 2015-2021 the original authors. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# https://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# + +############################################################################## +# +# Gradle start up script for POSIX generated by Gradle. +# +# Important for running: +# +# (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is +# noncompliant, but you have some other compliant shell such as ksh or +# bash, then to run this script, type that shell name before the whole +# command line, like: +# +# ksh Gradle +# +# Busybox and similar reduced shells will NOT work, because this script +# requires all of these POSIX shell features: +# * functions; +# * expansions «$var», «${var}», «${var:-default}», «${var+SET}», +# «${var#prefix}», «${var%suffix}», and «$( cmd )»; +# * compound commands having a testable exit status, especially «case»; +# * various built-in commands including «command», «set», and «ulimit». +# +# Important for patching: +# +# (2) This script targets any POSIX shell, so it avoids extensions provided +# by Bash, Ksh, etc; in particular arrays are avoided. +# +# The "traditional" practice of packing multiple parameters into a +# space-separated string is a well documented source of bugs and security +# problems, so this is (mostly) avoided, by progressively accumulating +# options in "$@", and eventually passing that to Java. +# +# Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS, +# and GRADLE_OPTS) rely on word-splitting, this is performed explicitly; +# see the in-line comments for details. +# +# There are tweaks for specific operating systems such as AIX, CygWin, +# Darwin, MinGW, and NonStop. +# +# (3) This script is generated from the Groovy template +# https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt +# within the Gradle project. +# +# You can find Gradle at https://github.com/gradle/gradle/. +# +############################################################################## + +# Attempt to set APP_HOME + +# Resolve links: $0 may be a link +app_path=$0 + +# Need this for daisy-chained symlinks. +while + APP_HOME=${app_path%"${app_path##*/}"} # leaves a trailing /; empty if no leading path + [ -h "$app_path" ] +do + ls=$( ls -ld "$app_path" ) + link=${ls#*' -> '} + case $link in #( + /*) app_path=$link ;; #( + *) app_path=$APP_HOME$link ;; + esac +done + +# This is normally unused +# shellcheck disable=SC2034 +APP_BASE_NAME=${0##*/} +APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit + +# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. +DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"' + +# Use the maximum available, or set MAX_FD != -1 to use that value. +MAX_FD=maximum + +warn () { + echo "$*" +} >&2 + +die () { + echo + echo "$*" + echo + exit 1 +} >&2 + +# OS specific support (must be 'true' or 'false'). +cygwin=false +msys=false +darwin=false +nonstop=false +case "$( uname )" in #( + CYGWIN* ) cygwin=true ;; #( + Darwin* ) darwin=true ;; #( + MSYS* | MINGW* ) msys=true ;; #( + NONSTOP* ) nonstop=true ;; +esac + +CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar + + +# Determine the Java command to use to start the JVM. +if [ -n "$JAVA_HOME" ] ; then + if [ -x "$JAVA_HOME/jre/sh/java" ] ; then + # IBM's JDK on AIX uses strange locations for the executables + JAVACMD=$JAVA_HOME/jre/sh/java + else + JAVACMD=$JAVA_HOME/bin/java + fi + if [ ! -x "$JAVACMD" ] ; then + die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME + +Please set the JAVA_HOME variable in your environment to match the +location of your Java installation." + fi +else + JAVACMD=java + which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. + +Please set the JAVA_HOME variable in your environment to match the +location of your Java installation." +fi + +# Increase the maximum file descriptors if we can. +if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then + case $MAX_FD in #( + max*) + # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked. + # shellcheck disable=SC3045 + MAX_FD=$( ulimit -H -n ) || + warn "Could not query maximum file descriptor limit" + esac + case $MAX_FD in #( + '' | soft) :;; #( + *) + # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked. + # shellcheck disable=SC3045 + ulimit -n "$MAX_FD" || + warn "Could not set maximum file descriptor limit to $MAX_FD" + esac +fi + +# Collect all arguments for the java command, stacking in reverse order: +# * args from the command line +# * the main class name +# * -classpath +# * -D...appname settings +# * --module-path (only if needed) +# * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables. + +# For Cygwin or MSYS, switch paths to Windows format before running java +if "$cygwin" || "$msys" ; then + APP_HOME=$( cygpath --path --mixed "$APP_HOME" ) + CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" ) + + JAVACMD=$( cygpath --unix "$JAVACMD" ) + + # Now convert the arguments - kludge to limit ourselves to /bin/sh + for arg do + if + case $arg in #( + -*) false ;; # don't mess with options #( + /?*) t=${arg#/} t=/${t%%/*} # looks like a POSIX filepath + [ -e "$t" ] ;; #( + *) false ;; + esac + then + arg=$( cygpath --path --ignore --mixed "$arg" ) + fi + # Roll the args list around exactly as many times as the number of + # args, so each arg winds up back in the position where it started, but + # possibly modified. + # + # NB: a `for` loop captures its iteration list before it begins, so + # changing the positional parameters here affects neither the number of + # iterations, nor the values presented in `arg`. + shift # remove old arg + set -- "$@" "$arg" # push replacement arg + done +fi + +# Collect all arguments for the java command; +# * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of +# shell script including quotes and variable substitutions, so put them in +# double quotes to make sure that they get re-expanded; and +# * put everything else in single quotes, so that it's not re-expanded. + +set -- \ + "-Dorg.gradle.appname=$APP_BASE_NAME" \ + -classpath "$CLASSPATH" \ + org.gradle.wrapper.GradleWrapperMain \ + "$@" + +# Stop when "xargs" is not available. +if ! command -v xargs >/dev/null 2>&1 +then + die "xargs is not available" +fi + +# Use "xargs" to parse quoted args. +# +# With -n1 it outputs one arg per line, with the quotes and backslashes removed. +# +# In Bash we could simply go: +# +# readarray ARGS < <( xargs -n1 <<<"$var" ) && +# set -- "${ARGS[@]}" "$@" +# +# but POSIX shell has neither arrays nor command substitution, so instead we +# post-process each arg (as a line of input to sed) to backslash-escape any +# character that might be a shell metacharacter, then use eval to reverse +# that process (while maintaining the separation between arguments), and wrap +# the whole thing up as a single "set" statement. +# +# This will of course break if any of these variables contains a newline or +# an unmatched quote. +# + +eval "set -- $( + printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" | + xargs -n1 | + sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' | + tr '\n' ' ' + )" '"$@"' + +exec "$JAVACMD" "$@" diff --git a/gradlew.bat b/gradlew.bat new file mode 100644 index 0000000..93e3f59 --- /dev/null +++ b/gradlew.bat @@ -0,0 +1,92 @@ +@rem +@rem Copyright 2015 the original author or authors. +@rem +@rem Licensed under the Apache License, Version 2.0 (the "License"); +@rem you may not use this file except in compliance with the License. +@rem You may obtain a copy of the License at +@rem +@rem https://www.apache.org/licenses/LICENSE-2.0 +@rem +@rem Unless required by applicable law or agreed to in writing, software +@rem distributed under the License is distributed on an "AS IS" BASIS, +@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +@rem See the License for the specific language governing permissions and +@rem limitations under the License. +@rem + +@if "%DEBUG%"=="" @echo off +@rem ########################################################################## +@rem +@rem Gradle startup script for Windows +@rem +@rem ########################################################################## + +@rem Set local scope for the variables with windows NT shell +if "%OS%"=="Windows_NT" setlocal + +set DIRNAME=%~dp0 +if "%DIRNAME%"=="" set DIRNAME=. +@rem This is normally unused +set APP_BASE_NAME=%~n0 +set APP_HOME=%DIRNAME% + +@rem Resolve any "." and ".." in APP_HOME to make it shorter. +for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi + +@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. +set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m" + +@rem Find java.exe +if defined JAVA_HOME goto findJavaFromJavaHome + +set JAVA_EXE=java.exe +%JAVA_EXE% -version >NUL 2>&1 +if %ERRORLEVEL% equ 0 goto execute + +echo. +echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. +echo. +echo Please set the JAVA_HOME variable in your environment to match the +echo location of your Java installation. + +goto fail + +:findJavaFromJavaHome +set JAVA_HOME=%JAVA_HOME:"=% +set JAVA_EXE=%JAVA_HOME%/bin/java.exe + +if exist "%JAVA_EXE%" goto execute + +echo. +echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% +echo. +echo Please set the JAVA_HOME variable in your environment to match the +echo location of your Java installation. + +goto fail + +:execute +@rem Setup the command line + +set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar + + +@rem Execute Gradle +"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %* + +:end +@rem End local scope for the variables with windows NT shell +if %ERRORLEVEL% equ 0 goto mainEnd + +:fail +rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of +rem the _cmd.exe /c_ return code! +set EXIT_CODE=%ERRORLEVEL% +if %EXIT_CODE% equ 0 set EXIT_CODE=1 +if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE% +exit /b %EXIT_CODE% + +:mainEnd +if "%OS%"=="Windows_NT" endlocal + +:omega diff --git a/src/CoreBindings.kt b/src/CoreBindings.kt new file mode 100644 index 0000000..9213917 --- /dev/null +++ b/src/CoreBindings.kt @@ -0,0 +1,109 @@ +package moe.nea.lisp + +object CoreBindings { + val nil = LispData.LispNil + val def = LispData.externalRawCall { context, callsite, stackFrame, args -> + if (args.size != 2) { + return@externalRawCall context.reportError("Function define expects exactly two arguments", callsite) + } + val (name, value) = args + if (name !is LispAst.Reference) { + return@externalRawCall context.reportError("Define expects a name as first argument", name) + } + if (name.label in stackFrame.variables) { + return@externalRawCall context.reportError("Cannot redefine value in local context", name) + } + return@externalRawCall stackFrame.setValueLocal(name.label, context.resolveValue(stackFrame, value)) + } + + val pure = LispData.externalCall { args, reportError -> + return@externalCall args.singleOrNull()?.let { value -> + LispData.externalCall { args, reportError -> + if (args.isNotEmpty()) + reportError("Pure function does not expect arguments") + else + value + } + } ?: reportError("Function pure expects exactly one argument") + } + + val lambda = LispData.externalRawCall { context, callsite, stackFrame, args -> + if (args.size != 2) { + return@externalRawCall context.reportError("Lambda needs exactly 2 arguments", callsite) + } + val (argumentNames, body) = args + if (argumentNames !is LispAst.Parenthesis) { + return@externalRawCall context.reportError("Lambda has invalid argument declaration", argumentNames) + } + val argumentNamesString = argumentNames.items.map { + val ref = it as? LispAst.Reference + if (ref == null) { + return@externalRawCall context.reportError("Lambda has invalid argument declaration", it) + } + ref.label + } + if (body !is LispAst.Parenthesis) { + return@externalRawCall context.reportError("Lambda has invalid body declaration", body) + } + LispData.createLambda(stackFrame, argumentNamesString, body) + } + + val defun = LispData.externalRawCall { context, callSite, stackFrame, lispAsts -> + if (lispAsts.size != 3) { + return@externalRawCall context.reportError("Invalid function definition", callSite) + } + val (name, args, body) = lispAsts + if (name !is LispAst.Reference) { + return@externalRawCall context.reportError("Invalid function definition name", name) + } + if (name.label in stackFrame.variables) { + return@externalRawCall context.reportError("Cannot redefine function in local context", name) + } + if (args !is LispAst.Parenthesis) { + return@externalRawCall context.reportError("Invalid function definition arguments", args) + } + val argumentNames = args.items.map { + val ref = it as? LispAst.Reference + ?: return@externalRawCall context.reportError("Invalid function definition argument name", it) + ref.label + } + if (body !is LispAst.Parenthesis) { + return@externalRawCall context.reportError("Invalid function definition body", body) + } + return@externalRawCall stackFrame.setValueLocal( + name.label, + LispData.createLambda(stackFrame, argumentNames, body, name.label) + ) + } + val seq = LispData.externalRawCall { context, callsite, stackFrame, args -> + var lastResult: LispData? = null + for (arg in args) { + lastResult = context.executeLisp(stackFrame, arg) + } + lastResult ?: context.reportError("Seq cannot be invoked with 0 argumens", callsite) + } + val debuglog = LispData.externalRawCall { context, callsite, stackFrame, args -> + println(args.joinToString(" ") { arg -> + when (val resolved = context.resolveValue(stackFrame, arg)) { + is LispData.Atom -> ":${resolved.label}" + is LispData.JavaExecutable -> "" + LispData.LispNil -> "nil" + is LispData.LispNumber -> resolved.number.toString() + is LispData.LispNode -> resolved.node.toSource() + is LispData.LispObject<*> -> resolved.data.toString() + is LispData.LispInterpretedCallable -> "" + } + }) + LispData.LispNil + } + + fun offerAllTo(bindings: StackFrame) { + bindings.setValueLocal("nil", nil) + bindings.setValueLocal("def", def) + bindings.setValueLocal("pure", pure) + bindings.setValueLocal("lambda", lambda) + bindings.setValueLocal("defun", defun) + bindings.setValueLocal("seq", seq) + bindings.setValueLocal("debuglog", debuglog) + } +} \ No newline at end of file diff --git a/src/LispAst.kt b/src/LispAst.kt new file mode 100644 index 0000000..79fee8a --- /dev/null +++ b/src/LispAst.kt @@ -0,0 +1,41 @@ +package moe.nea.lisp + +sealed class LispAst : HasLispPosition { + + + abstract fun toSource(): String + + + data class Program(override val position: LispPosition, val nodes: List) : LispAst() { + override fun toSource(): String { + return nodes.joinToString("\n") { + it.toSource() + } + } + } + + sealed class LispNode : LispAst() + data class Atom(override val position: LispPosition, val label: String) : LispNode() { + override fun toSource(): String { + return ":$label" + } + } + + data class Reference(override val position: LispPosition, val label: String) : LispNode() { + override fun toSource(): String { + return label + } + } + + data class Parenthesis(override val position: LispPosition, val items: List) : LispNode() { + override fun toSource(): String { + return items.joinToString(" ", "(", ")") { it.toSource() } + } + } + + data class StringLiteral(override val position: LispPosition, val parsedString: String) : LispNode() { + override fun toSource(): String { + return "\"${parsedString.replace("\\", "\\\\").replace("\"", "\\\"")}\"" // TODO: better escaping + } + } +} diff --git a/src/LispData.kt b/src/LispData.kt new file mode 100644 index 0000000..1f13ad3 --- /dev/null +++ b/src/LispData.kt @@ -0,0 +1,105 @@ +package moe.nea.lisp + +sealed class LispData { + + fun lispCastObject(lClass: LispClass): LispObject? { + if (this !is LispObject<*>) return null + if (this.handler != lClass) return null + return this as LispObject + } + + object LispNil : LispData() + data class Atom(val label: String) : LispData() + data class LispNode(val node: LispAst.LispNode) : LispData() + data class LispNumber(val number: Double) : LispData() + data class LispObject(val data: T, val handler: LispClass) : LispData() + sealed class LispExecutable() : LispData() { + abstract fun execute( + executionContext: LispExecutionContext, + callsite: LispAst.LispNode, + stackFrame: StackFrame, + args: List + ): LispData + } + + + abstract class JavaExecutable : LispExecutable() { + } + + data class LispInterpretedCallable( + val declarationStackFrame: StackFrame, + val argNames: List, + val body: LispAst.Parenthesis, + val name: String?, + ) : LispExecutable() { + override fun execute( + executionContext: LispExecutionContext, + callsite: LispAst.LispNode, + stackFrame: StackFrame, + args: List + ): LispData { + if (argNames.size != args.size) { + TODO("ERROR") + } + val invocationFrame = declarationStackFrame.fork() + + for ((name, value) in argNames.zip(args)) { + invocationFrame.setValueLocal(name, executionContext.resolveValue(stackFrame, value)) + } + return executionContext.executeLisp(invocationFrame, body) + } + } + + interface LispClass { + fun access(obj: T, name: String): LispData + fun instantiate(obj: T) = LispObject(obj, this) + } + + object LispStringClass : LispClass { + override fun access(obj: String, name: String): LispData { + return LispNil + } + } + + companion object { + fun string(value: String): LispObject = + LispStringClass.instantiate(value) + + fun externalRawCall(callable: (context: LispExecutionContext, callsite: LispAst.LispNode, stackFrame: StackFrame, args: List) -> LispData): LispExecutable { + return object : JavaExecutable() { + override fun execute( + executionContext: LispExecutionContext, + callsite: LispAst.LispNode, + stackFrame: StackFrame, + args: List + ): LispData { + return callable.invoke(executionContext, callsite, stackFrame, args) + } + } + } + + fun externalCall(callable: (args: List, reportError: (String) -> LispData) -> LispData): LispExecutable { + return object : JavaExecutable() { + override fun execute( + executionContext: LispExecutionContext, + callsite: LispAst.LispNode, + stackFrame: StackFrame, + args: List + ): LispData { + val mappedArgs = args.map { executionContext.resolveValue(stackFrame, it) } + return callable.invoke(mappedArgs) { executionContext.reportError(it, callsite) } + } + } + } + + + fun createLambda( + declarationStackFrame: StackFrame, + args: List, + body: LispAst.Parenthesis, + nameHint: String? = null, + ): LispExecutable { + return LispInterpretedCallable(declarationStackFrame, args, body, nameHint) + } + } +} diff --git a/src/LispErrorReporter.kt b/src/LispErrorReporter.kt new file mode 100644 index 0000000..d9ad148 --- /dev/null +++ b/src/LispErrorReporter.kt @@ -0,0 +1,15 @@ +package moe.nea.lisp + +class LispErrorReporter { + + data class LispError(val name: String, val position: LispPosition) + + + val errors = listOf() + + fun reportError(name: String, position: HasLispPosition) { + println("LISP ERROR: $name at ${position.position}") + } + + +} diff --git a/src/LispExecutionContext.kt b/src/LispExecutionContext.kt new file mode 100644 index 0000000..f169ba9 --- /dev/null +++ b/src/LispExecutionContext.kt @@ -0,0 +1,61 @@ +package moe.nea.lisp + +class LispExecutionContext() { + + private val errorReporter = LispErrorReporter() + private val rootStackFrame = StackFrame(null) + + + fun reportError(name: String, position: HasLispPosition): LispData.LispNil { + println("Error: $name ${position.position}") + return LispData.LispNil + } + + + fun genBindings(): StackFrame { + return StackFrame(rootStackFrame) + } + + fun executeProgram(stackFrame: StackFrame, program: LispAst.Program) { + for (node in program.nodes) { + executeLisp(stackFrame, node) + } + } + + + fun executeLisp(stackFrame: StackFrame, node: LispAst.LispNode): LispData { + when (node) { + is LispAst.Parenthesis -> { + val first = node.items.firstOrNull() + ?: return reportError("Cannot execute empty parenthesis ()", node) + + val rest = node.items.drop(1) + return when (val resolvedValue = resolveValue(stackFrame, first)) { + is LispData.Atom -> reportError("Cannot execute atom", node) + LispData.LispNil -> reportError("Cannot execute nil", node) + is LispData.LispNumber -> reportError("Cannot execute number", node) + is LispData.LispNode -> reportError("Cannot execute node", node) + is LispData.LispObject<*> -> reportError("Cannot execute object-value", node) + is LispData.LispExecutable -> { + resolvedValue.execute(this, node, stackFrame, rest) + } + } + + } + + else -> return reportError("Expected invocation", node) + } + } + + fun resolveValue(stackFrame: StackFrame, node: LispAst.LispNode): LispData { + return when (node) { + is LispAst.Atom -> LispData.Atom(node.label) + is LispAst.Parenthesis -> executeLisp(stackFrame, node) + is LispAst.Reference -> stackFrame.resolveReference(node.label) + ?: reportError("Could not resolve variable ${node.label}", node) + + is LispAst.StringLiteral -> LispData.string(node.parsedString) + } + } +} + diff --git a/src/LispParser.kt b/src/LispParser.kt new file mode 100644 index 0000000..1117397 --- /dev/null +++ b/src/LispParser.kt @@ -0,0 +1,116 @@ +package moe.nea.lisp + +import java.io.File + +class LispParser private constructor(filename: String, string: String) { + val racer = StringRacer(filename, string) + val program = parseProgram() + + companion object { + fun parse(filename: String, string: String): LispAst.Program { + return LispParser(filename, string).program + } + fun parse(file: File): LispAst.Program { + return parse(file.absolutePath, file.readText()) + } + + val digits = "1234567890" + val alphabet = "abcdefghijklmnopqrstuvwxyz" + val validStartingIdentifiers = "-.#+*'!$%&/=?_~|^" + alphabet + alphabet.uppercase() + val validIdentifiers = validStartingIdentifiers + digits + val parenthesisMatches = mapOf( + "(" to ")", + "[" to "]", + "{" to "}", + "<" to ">", + ) + } + + fun parseProgram(): LispAst.Program { + val start = racer.idx + val nodes = mutableListOf() + while (true) { + racer.skipWhitespace() + if (racer.finished()) + break + nodes.add(parseNode()) + } + return LispAst.Program(racer.span(start), nodes) + } + + private fun parseNode(): LispAst.LispNode { + val start = racer.idx + val paren = racer.peekReq(1) ?: racer.error("Expected start of expression") + val matchingParen = parenthesisMatches[paren] + if (matchingParen != null) { + val paren = parseParenthesis(paren, matchingParen) + return LispAst.Parenthesis(racer.span(start), paren) + } + if (paren == "\"") { + return parseString() + } + if (paren == ":") { + return parseAtom() + } + val ident = parseIdentifier() + return LispAst.Reference(racer.span(start), ident) + } + + + fun parseAtom(): LispAst.Atom { + val start = racer.idx + racer.expect(":", "Expected : at start of atom") + val ident = parseIdentifier() + return LispAst.Atom(racer.span(start), ident) + } + + + fun parseIdentifier(): String { + return racer.consumeWhile { it.first() in validStartingIdentifiers && it.last() in validIdentifiers }.also { + if (it.isEmpty()) racer.error("Expected identifier") + } + } + + fun parseString(): LispAst.StringLiteral { + val start = racer.idx + val quoted = parseQuotedString() + return LispAst.StringLiteral(racer.span(start), quoted) + } + + fun parseQuotedString(): String { + racer.expect("\"", "Expected '\"' at string start") + val sb = StringBuilder() + while (true) { + when (val peek = racer.consumeCountReq(1)) { + "\"" -> break + "\\" -> { + val escaped = racer.consumeCountReq(1) ?: racer.error("Unfinished backslash escape") + if (escaped != "\"" && escaped != "\\") { + // Surprisingly i couldn't find unicode escapes to be generated by the original minecraft 1.8.9 implementation + racer.idx-- + racer.error("Invalid backslash escape '$escaped'") + } + sb.append(escaped) + } + + null -> racer.error("Unfinished string") + else -> { + sb.append(peek) + } + } + } + return sb.toString() + } + + private fun parseParenthesis(opening: String, closing: String): List { + val l = mutableListOf() + racer.expect(opening, "Expected $opening") + while (true) { + racer.skipWhitespace() + if (racer.tryConsume(closing)) { + return l + } + l.add(parseNode()) + } + } +} diff --git a/src/LispParsingError.kt b/src/LispParsingError.kt new file mode 100644 index 0000000..f6e76de --- /dev/null +++ b/src/LispParsingError.kt @@ -0,0 +1,4 @@ +package moe.nea.lisp + +data class LispParsingError(val baseString: String, val offset: Int, val mes0: String) : + Exception("$mes0 at $offset in `$baseString`.") \ No newline at end of file diff --git a/src/LispPosition.kt b/src/LispPosition.kt new file mode 100644 index 0000000..ea901a2 --- /dev/null +++ b/src/LispPosition.kt @@ -0,0 +1,21 @@ +package moe.nea.lisp + +data class LispPosition( + val start: Int, + val end: Int, + val fileName: String, + val fileContent: String, +) : HasLispPosition { + val startLine by lazy { fileContent.substring(0, start).count { it == '\n' } + 1 } + val startColumn by lazy { start - fileContent.substring(0, start).indexOfLast { it == '\n' } } + val endLine by lazy { fileContent.substring(0, end).count { it == '\n' } + 1 } + val endColumn by lazy { end - fileContent.substring(0, end).indexOfLast { it == '\n' } } + override val position get() = this + override fun toString(): String { + return "at $fileName:$startLine:$startColumn until $endLine:$endColumn" + } +} + +interface HasLispPosition { + val position: LispPosition +} diff --git a/src/StackFrame.kt b/src/StackFrame.kt new file mode 100644 index 0000000..66d74b2 --- /dev/null +++ b/src/StackFrame.kt @@ -0,0 +1,32 @@ +package moe.nea.lisp + +class StackFrame(val parent: StackFrame?) { + + val variables = mutableMapOf() + + interface MetaKey + + private val meta: MutableMap, Any> = mutableMapOf() + + fun getMeta(key: MetaKey): T? { + return meta[key] as? T + } + + fun setMeta(key: MetaKey, value: T) { + meta[key] = value + } + + fun resolveReference(label: String): LispData? = + variables[label] ?: parent?.resolveReference(label) + + fun setValueLocal(label: String, value: LispData): LispData { + variables[label] = value + return value + } + + fun fork(): StackFrame { + return StackFrame(this) + } + + +} diff --git a/src/StringRacer.kt b/src/StringRacer.kt new file mode 100644 index 0000000..d0a4a15 --- /dev/null +++ b/src/StringRacer.kt @@ -0,0 +1,81 @@ +package moe.nea.lisp + +import java.util.* + +class StringRacer(val filename: String, val backing: String) { + var idx = 0 + val stack = Stack() + + fun pushState() { + stack.push(idx) + } + + fun popState() { + idx = stack.pop() + } + + fun span(start: Int) = LispPosition(start, idx, filename, backing) + + fun discardState() { + stack.pop() + } + + fun peek(count: Int): String { + return backing.substring(minOf(idx, backing.length), minOf(idx + count, backing.length)) + } + + fun finished(): Boolean { + return peek(1).isEmpty() + } + + fun peekReq(count: Int): String? { + val p = peek(count) + if (p.length != count) + return null + return p + } + + fun consumeCountReq(count: Int): String? { + val p = peekReq(count) + if (p != null) + idx += count + return p + } + + fun tryConsume(string: String): Boolean { + val p = peek(string.length) + if (p != string) + return false + idx += p.length + return true + } + + fun consumeWhile(shouldConsumeThisString: (String) -> Boolean): String { + var lastString: String = "" + while (true) { + val nextPart = peek(1) + if (nextPart.isEmpty()) break + val nextString = lastString + nextPart + if (!shouldConsumeThisString(nextString)) { + break + } + idx++ + lastString = nextString + } + return lastString + } + + fun expect(search: String, errorMessage: String) { + if (!tryConsume(search)) + error(errorMessage) + } + + fun error(errorMessage: String): Nothing { + throw LispParsingError(backing, idx, errorMessage) + } + + fun skipWhitespace() { + consumeWhile { Character.isWhitespace(it.last()) } + } +} + diff --git a/test/res/test.lisp b/test/res/test.lisp new file mode 100644 index 0000000..f3d21d9 --- /dev/null +++ b/test/res/test.lisp @@ -0,0 +1,11 @@ +(debuglog "Hello, World, here is an atom:" :iamanatom) +(defun myfun (var) (debuglog var)) +(myfun :myfunworks) +((lambda (a) (debuglog a)) :atom) +(debuglog a) +(def helloworld (pure "hello world")) +(debuglog helloworld (helloworld)) +(defun + () (seq + (debuglog "also multiplication") + (debuglog "addition"))) +(debuglog +) diff --git a/test/src/TestLisp.kt b/test/src/TestLisp.kt new file mode 100644 index 0000000..f986f1c --- /dev/null +++ b/test/src/TestLisp.kt @@ -0,0 +1,14 @@ +import moe.nea.lisp.CoreBindings +import moe.nea.lisp.LispExecutionContext +import moe.nea.lisp.LispParser +import java.io.File + +object T + +fun main() { + val otherP = LispParser.parse(File(T::class.java.getResource("/test.lisp")!!.file)) + val executionContext = LispExecutionContext() + val bindings = executionContext.genBindings() + CoreBindings.offerAllTo(bindings) + executionContext.executeProgram(bindings, otherP) +} -- cgit