Boolean, Integer,  Real, String
false,         0,   0.0,    "0"
true,          1,   1.0,    "1"
Integer, Integer,  Real,   Real
+0,           -0,  +0.0,   -0.0
+3,           -3, +3.14,  -3.14
Boolean, Character, Relatif, Regex
false,         'f',      0R,   [0]
Date,        Time
20000101,00:00:00
