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README.md

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+	This product is developed at the second-grade course, Informatic Science Basic Experiment class at the University of Tokyo.
+
+# Picrin - a lightweight scheme interpreter
+
+## Freatures
+
+- R7RS compatibility (but partial support)
+- reentrant design (all VM states are stored in single global state object)
+- bytecode interpreter (based on Stack VM technology)
+- direct threading VM
+- exact GC (simple mark and sweep strategy)
+
+## How to use it
+
+- build
+
+		$ make build
+
+	built executable binary will be under bin/ directory.
+
+- run
+
+	Simply directly run the binary `bin/picrin` from terminal, or you can use `make` to execute it like this.
+
+		$ make run
+	
+In the default option, when `make` command is called without arguments, it builds the binary and right after that dropped into the picrin interactive shell (REPL).
+
+## Authors
+
+Yuichi Nishiwaki (yuichi.nishiwaki at gmail.com)