README.md

README.md

@@ -1,3 +1,38 @@
 # SCL: Simple Calculator Language
 
-A spiritual successor to halk.
+## Syntax
+
+As one would expect, you can evaluate simple infix expressions:
+
+```scl
+> 1 + 1
+= 2
+```
+
+You can also define your own functions:
+
+```scl
+> f(x) 2x
+> f(2)
+= 4
+```
+
+SCL will dynamically decide on types, but you can state them explicitly as
+well:
+
+```scl
+> f(x:int) 2x
+> f(2.2)
+! f(x:int): x must be of type int.
+```
+
+Variables can be defined, with several attributes:
+
+```scl
+> a = 1             // Interpret type automatically.
+> b:int = 1         // Must be int.
+> c:const:int = 1   // Constant: value can never change.
+> d:lazy = (1 + 1)  // Interpreter will wait as long as possible before
+                    // evaluating.
+```
+