Ruby: step0, step1

1 files changed, 25 insertions, 0 deletions

diff --git a/ruby/step0_repl.rb b/ruby/step0_repl.rb
new file mode 100644
index 0000000..dd32b27
--- /dev/null
+++ b/ruby/step0_repl.rb
@@ -0,0 +1,25 @@
+require "readline"
+
+# read
+def READ(str)
+    return str
+end
+
+# eval
+def EVAL(ast, env)
+    return ast
+end
+
+# print
+def PRINT(exp)
+    return exp
+end
+
+# repl
+def REP(str)
+    return PRINT(EVAL(READ(str), {}))
+end
+
+while line = Readline.readline("user> ", true)
+    puts REP(line)
+end