Add resolution document for #135 (Add Dict/Tuple to the core)

solutions/language/Value-Types.md

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+# Basic Value Type Structures In Raku
+
+## Preface
+
+This resolution is based upon discussion in 
+[problem-solving#135](https://github.com/Raku/problem-solving/issues/135) and,
+accordingly, provides a solution to the issue.
+
+The issue was opened as a followup to unification of behaviors of `List` and
+`Map` structures which resulted in both types preserving containerization of
+their elements. This resulted in both types becoming non-value types,
+effectively leaving Raku without value type positional and associative
+structures.
+
+## Solution
+
+Two new types are to be added to the Raku language:
+
+- `ValueList` to represent immutable positional value type
+- `ValueMap` to represent immutable associative value type
+
+Both types are characterized by forcible scalar de-containerization of any
+object, stored in them. For example, here is how it must work with lists:
+
+    my $val = 42;
+    my $l := List.new($val);
+    say $l[0].VAR.^name; # Scalar
+    my $vl := ValueList.new($val);
+    say $vl[0].VAR.^name; # Int
+
+It also means that for any `Value*`-type structures instances of any non-value
+type classes, including but not limited to `Array` and `Hash`, are considered
+the same value if they're the same object, not if their content is identical.
+
+### Parametrization
+
+The `Value*` types must remain non-parameterizable. Alongside with `List` and
+`Map` they must provide basic functionality, sufficient to be extended with
+their sub-classes in ways `Array` and `Hash` do it.
+
+## Reasoning 
+
+Provide means for operators like `===`, types like `QuantHash`-es, and other
+value-type based language entities to easily operate on positional and
+associative type structures.
+
+## Language Version Eligibility
+
+Both types are to be available no earlier than in Raku v6.e.