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README.md

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+# cat-disruptor-6500
+
+A Discord bot that reacts to certain messages with certain emojis. More importantly, it also lets you write code!
+
+## Commands:
+
+!START - start the interpreter
+
+!STOP - stop the interpreter
+
+LIST - list all code in memory
+
+SAVE filename - save code into database
+
+LOAD filename - load filename into memory
+
+Code is specified by writing `line_num code`. For example, `10 print "hello world"`. This makes it easy to insert new code or overwrite lines.
+
+### Example session
+
+```
+!START
+10 for x in 0 to 10
+20 print x
+RUN
+> expected NEXT after FOR statement. # oops - we forgot a line
+30 next x
+LIST
+> 10 for x in 0 to 10
+> 20 print x
+> 30 next x
+RUN
+> 0
+> 1
+> 2
+> 3
+> 4
+> 5
+> 6
+> 7
+> 8
+> 9
+> 10
+# actually, let's print them all on the same line
+5 a = ""
+20 a += x
+LIST
+> 5 a = ""
+> 10 for x in 0 to 10
+> 20 a += x
+> 30 next x
+RUN
+012345678910 # oops - let's add spaces
+20 a += " " + x
+RUN
+> 0 1 2 3 4 5 6 7 8 9 10 # awesome! let's save this program
+SAVE count_to_ten
+> Saved as count_to_ten
+```
+
+The interpreter can execute arbitrary code safely - it includes CPU and memory limits. For information on syntax, check out the xBASIC interpreter: https://git.scd31.com/stephen/xbasic
+
+It even does graphics!
+
+![Example session](https://git.scd31.com/stephen/cat-disruptor-6500/raw/branch/master/example.png)