With typesig Without typesig
Before seq
map id direct
Without let _ _ _
With let _ _ "abc"
map id direct
Without let _ _ "abc"
With let _ _ "abc"
After seq
map id direct
Without let _ : _ _ : _ _
With let _ : _ "abc" "abc"
map id direct
Without let _ : _ "abc" "abc"
With let _ : _ "abc" "abc"

Snippets:
map:map succ ['a'..'c']
id:id ['a','b','c']
direct:['a','b','c']
Forms:
With typesig without let:a :: [Char] ; a = ...
With typesig with let:let a :: [Char] ; a = ...
Without typesig without let:a = ...
Without typesig with let:let a = ...
Execution: 
ghci> let a = map succ ['a'..'c']   -- or other snippet in other form
ghci> :sprint a
a = _                               -- before seq
ghci> seq a ()
ghci> :sprint a
a = _ : _                           -- after seq
Interpretations: