added a beanshell interpreter experiment

beanshell/src/prog8beanshell/CommandLineReader.kt

@@ -0,0 +1,48 @@
+package prog8beanshell
+
+import java.io.FilterReader
+import java.io.Reader
+
+
+class CommandLineReader(val input: Reader): FilterReader(input)  {
+    private val normal = 0
+    private val lastCharNL = 1
+    private val sentSemi = 2
+    private var state = lastCharNL
+
+    override fun read(): Int {
+        if (state == sentSemi) {
+            this.state = lastCharNL
+            return 10
+        } else {
+            var b = input.read()
+            while(b==13) b = input.read()
+
+            if (b == 10) {
+                if (this.state == lastCharNL) {
+                    b = 59
+                    this.state = sentSemi
+                } else {
+                    this.state = lastCharNL
+                }
+            } else {
+                this.state = normal
+            }
+
+            return b
+        }
+
+    }
+
+    override fun read(buff: CharArray, off: Int, len: Int): Int {
+        val b = read()
+        if (b == -1) {
+            return -1
+        } else {
+            buff[off] = b.toChar()
+            return 1
+        }
+
+    }
+}
+