NOTES

- from latin-1 suppliment
    [¬×]

- from General Punctuation
    [‖]

- from Arrows (not for operators!)
    [→⇒]

- from Mathematical Operators
    (don't use forall, infinity for user defined operators!)
    [\x2201-\x221D\x221F-\x22FF]

- from Misc Tech Block
    [⌈⌉⌊⌋]

- from Geometric Shapes
    [▷◁]

- from Miscellaneous Mathematical Symbols-A
    [⟂]

Unicode chars, code points and ASCII equivalents
    - ¬ 00AC \not
    - × 00D7 *
    - ‖ 2016 \norm
    - → 2192 ->
    - ⇒ 21D2 =>
    - ∀ 2200 \forall
    - ∙ 2219 \dot
    - √ 221A \sqrt()
    - ∧ 2227 \and
    - ∨ 2228 \or
    - ≠ 2260 !=
    - ≤ 2264 <=
    - ≥ 2265 >=
    - ⊕ 2295 \xor
    - ⌈ 2308 \ceiling()
    - ⌉ 2309
    - ⌊ 230A \floor()
    - ⌋ 230B
    - ▷ 25B7 \max
    - ◁ 25C1 \min
    - ⟂ 27C2 \perp (*)

    (*)  must add to DejaVu Sans Mono

Feedback (p1 : (α, γ) >> β, p2 : β >> γ) : α >> β
Feedback (p  : (α, β) >> β             ) : α >> β

Type coersion rules:
    Scalar -> Scalar (Integer -> Real ...)
    Scalar -> Tuple (duplicate Scalar type to make Tuple, then invoke Tuple -> Tuple)
    Scalar -> Record (First Scalar -> Tuple then Tuple -> Record)
    Tuple -> Scalar (Not allowed)
    Tuple -> Tuple (If same size and elements coerce recursively)
    Tuple -> Record (If same size and elements coerce recursively)
    Record -> Scalar (Not allowed)
    Record -> Tuple (Not allowed)
    Record -> Record (Not allowed)