Functions with independent (global) scopes

General Usage
8

You can spot global variables in functions with reflection, even something as simple as:

julia> foo() = sin(x) # oops I forgot to write `foo(x)`
foo (generic function with 1 method)

julia> @code_warntype foo()
MethodInstance for foo()
  from foo() in Main at REPL[12]:1
Arguments
  #self#::Core.Const(foo)
Body::Any
1 ─ %1 = Main.sin(Main.x)::Any
└──      return %1

But you need to distinguish the intended globals like Main.sin or the unintended globals like Main.x. You don’t have to do this much work if you get the habit of writing all the necessary arguments into a function header, it’s a good habit in any language.

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