#Truthiness:
# We already know that 0 is truthy
(true and 0) println
# Empty strings are apparently truthy
(true and "") println
# As are empty lists
(true and list()) println
# But nil is falsey
(true and nil) println
# So basically anything except `false` and `nil` is truthy

# = vs := vs ::=
# Obvious part so far is that you must create with := before being able to assign with plain =
myvar := Object clone
myvar println
myvar = Object clone
# Docs say:
#    ::= 	Creates slot, creates setter, assigns value
#    := 	Creates slot, assigns value
#    = 	Assigns value to slot if it exists, otherwise raises exception 
# But what is a "setter" in this context?
myvar foo ::= Object clone
myvar println
# It seems we get a "setX" method, which helps us do some things in certain contexts:
# https://stackoverflow.com/a/5977757

# What slots does a prototype support? Direct ones are human readable in the output
myvar proto println
# But they're not listed indirectly
SubClass := Object clone
myvar2 := SubClass clone
myvar2 proto println
# Can we find it out programattically?
# It's not recursive, but the type should tell us:
myvar2 type proto println
# Except the value of `type` is just a string (or Sequence in Io), so it doesn't
myvar2 type proto type println
# Or, of course, a Prototype is a named object that starts with a capital letter
# So we can just use slotNames to get them programmatically (but that only shows direct slots)
myvar slotNames println
# And to get the parent ones then we just chain "proto"
myvar proto slotNames println
myvar proto proto slotNames println
# If I knew enough Io then I'd do a recursion loop and walk up until proto == Object
# Update: See day2-reflection.io!



#Execute methods by slot name - use "perform"
SubClass method1 := method("Method 1 was called" println)
SubClass method2 := method("Method 2 was called" println)
myvar2 perform("method1")
myvar2 perform("method2")



# Is Io strongly or weakly typed?
(1 + 1) println
(1 + "one") println
# Exception: argument 0 to method '+' must be a Number, not a 'Sequence'
# Therefore strongly typed