evaluator: introduce and expose scope tracking

evaluator/src/main/kotlin/gay/pizza/pork/evaluator/CompilationUnitContext.kt

@@ -9,10 +9,11 @@ import gay.pizza.pork.frontend.ImportLocator
 class CompilationUnitContext(
   val compilationUnit: CompilationUnit,
   val evaluator: Evaluator,
-  rootScope: Scope
+  rootScope: Scope,
+  name: String = "unknown"
 ) {
-  val internalScope = rootScope.fork()
-  val externalScope = rootScope.fork()
+  val internalScope = rootScope.fork("internal $name")
+  val externalScope = rootScope.fork("external $name")
 
   private var initialized = false
 

evaluator/src/main/kotlin/gay/pizza/pork/evaluator/Evaluator.kt

@@ -14,7 +14,7 @@ class Evaluator(val world: World, val scope: Scope) {
     val unit = world.load(locator)
     val identity = world.stableIdentity(locator)
     val context = contexts.computeIfAbsent(identity) {
-      CompilationUnitContext(unit, this, scope)
+      CompilationUnitContext(unit, this, scope, name = "${locator.form} ${locator.path}")
     }
     context.initIfNeeded()
     return context

evaluator/src/main/kotlin/gay/pizza/pork/evaluator/Scope.kt

@@ -1,6 +1,10 @@
 package gay.pizza.pork.evaluator
 
-class Scope(val parent: Scope? = null, inherits: List<Scope> = emptyList()) {
+class Scope(
+  val parent: Scope? = null,
+  inherits: List<Scope> = emptyList(),
+  val name: String? = null
+) {
   private val inherited = inherits.toMutableList()
   private val variables = mutableMapOf<String, Any>()
 
@@ -41,8 +45,8 @@ class Scope(val parent: Scope? = null, inherits: List<Scope> = emptyList()) {
     return value
   }
 
-  fun fork(): Scope =
-    Scope(this)
+  fun fork(name: String? = null): Scope =
+    Scope(this, name = name)
 
   internal fun inherit(scope: Scope) {
     inherited.add(scope)
@@ -55,5 +59,26 @@ class Scope(val parent: Scope? = null, inherits: List<Scope> = emptyList()) {
     return parent
   }
 
+  fun crawlScopePath(
+    path: List<String> = mutableListOf(name ?: "unknown"),
+    block: (String, List<String>) -> Unit
+  ) {
+    for (key in variables.keys) {
+      block(key, path)
+    }
+
+    for (inherit in inherited) {
+      val mutablePath = path.toMutableList()
+      mutablePath.add("inherit ${inherit.name ?: "unknown"}")
+      inherit.crawlScopePath(mutablePath, block)
+    }
+
+    if (parent != null) {
+      val mutablePath = path.toMutableList()
+      mutablePath.add("parent ${parent.name ?: "unknown"}")
+      parent.crawlScopePath(mutablePath, block)
+    }
+  }
+
   private object NotFound
 }

examples/java.pork

@@ -1,13 +1,7 @@
 import java java.lang.System
 import java java.io.PrintStream
-import java java.io.InputStreamReader
-import java java.io.BufferedReader
 
 export func main() {
-  let input = java_lang_System_in_get()
-  let reader = java_io_InputStreamReader_new_inputstream(input)
-  let bufferedReader = java_io_BufferedReader_new_reader(reader)
-  let line = java_io_BufferedReader_readLine(bufferedReader)
   let stream = java_lang_System_err_get()
-  java_io_PrintStream_println_string(stream, line)
+  java_io_PrintStream_println_string(stream, "Hello World")
 }

tool/src/main/kotlin/gay/pizza/pork/tool/RunCommand.kt

@@ -5,10 +5,7 @@ import com.github.ajalt.clikt.parameters.arguments.argument
 import com.github.ajalt.clikt.parameters.options.flag
 import com.github.ajalt.clikt.parameters.options.option
 import gay.pizza.dough.fs.PlatformFsProvider
-import gay.pizza.pork.evaluator.Arguments
-import gay.pizza.pork.evaluator.CallableFunction
-import gay.pizza.pork.evaluator.None
-import gay.pizza.pork.evaluator.Scope
+import gay.pizza.pork.evaluator.*
 import gay.pizza.pork.ffi.JavaNativeProvider
 import gay.pizza.pork.ffi.JnaNativeProvider
 
@@ -16,6 +13,7 @@ class RunCommand : CliktCommand(help = "Run Program", name = "run") {
   val loop by option("--loop", help = "Loop Program").flag()
   val measure by option("--measure", help = "Measure Time").flag()
   val quiet by option("--quiet", help = "Silence Prints").flag()
+  val dumpScope by option("--dump-scope", help = "Dump Scope").flag()
   val path by argument("file")
 
   override fun run() {
@@ -36,6 +34,14 @@ class RunCommand : CliktCommand(help = "Run Program", name = "run") {
       addNativeFunctionProvider("java", JavaNativeProvider())
     })
 
+    if (dumpScope) {
+      val functionContext = main as FunctionContext
+      val internalScope = functionContext.compilationUnitContext.internalScope
+      internalScope.crawlScopePath { key, path ->
+        println("[scope] $key [${path.joinToString(" -> ")}]")
+      }
+    }
+
     maybeLoopAndMeasure(loop, measure) {
       main.call(Arguments(emptyList()))
     }