more docs

README.md

@@ -7,6 +7,39 @@ __current state of implementation and docs__:
 - [introduction and tutorial](docs/tutorial.md)
 - [math and operators](docs/math.md).
 
+## Integration in Kotlin multiplatform
+
+### Add library
+
+TBD
+
+### Execute script:
+
+```kotlin
+assertEquals("hello, world", eval(""" 
+    "hello, " + "world" 
+    """).toString())
+```
+
+### Exchanging information
+
+Script is executed over some `Context`. Create instance of the context,
+add your specific vars and functions to it, an call over it:
+
+```kotlin
+val context = Context().apply {
+    addFn("addArgs") {
+        var sum = 0.0
+        for( a in args) sum += a.toDouble()
+        ObjReal(sum)
+    }
+    addConst("LIGHT_SPEED", ObjReal(299_792_458.0))
+}
+
+context.eval("addArgs(1,2,3)") // <- 6
+```
+Note that the context stores all changes in it so you can make calls on a single context to preserve state between calls.
+
 ## Why? 
 
 Designed to add scripting to kotlin multiplatform application in easy and efficient way. This is attempt to achieve what Lua is for C/++.