Pointers and reference syntax

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+# Pointers and Reference Syntax
+
+- Created: 2016-05-08
+
+
+## Summary
+[Summary]: #summary
+
+I propose the universal star `*` operator.
+It works for all pointer related operations.
+
+```rebuild
+*x # pointer to variable/argument (address of)
+x* # dereference pointer
+
+*int # pointer to type
+```
+
+
+## Motivation
+[Motivation]: #motivation
+
+We need a basic set of syntax defined in order to present more in depth proposals to the language.
+
+Pointer handling seems inevitable in a compiled language.
+
+
+## Detailed design
+[Detailed design]: #detailed-design
+
+I propose the following syntax.
+
+1. A star in front of something is read as "pointer to".
+2. A star behind something is read as "dereference".
+
+The first rule works in type expressions and everything that an address can be taken of.
+For example: variables, arguments, functions and instance members.
+
+The second rule only applies to expressions which evaluate to pointers.
+
+These two rules are minimal and very consistent.
+That should make it very easy to teach.
+
+Some more examples:
+
+```rebuild
+fn f (x) -> bool; # declare a function f
+def pf = *f # pointer to function f
+pf*(n) # invocation of the function behind the pointer
+
+type i5 = *(5 of int) # pointer to array
+type p5 = 5 of *int # array of pointers
+```
+
+
+## Drawbacks
+[Drawbacks]: #drawbacks
+
+### The dereferencing star operator might be ambigous with multiplications.
+
+It does not make much sense to multiply a pointer with something.
+So this ambiguity should be easily resolvable.
+
+### The dereferencing star is ambigous for function invocations.
+
+It's unclear for the reader wether a function pointer is dereferenced or the function result is dereferenced.
+
+To mitigate the problem it should be illigal to dereference a function result without brackets around the function.
+
+```rebuild
+var a = f()* # function returns a pointer that is dereferenced
+```
+
+
+## Alternatives
+[Alternatives]: #alternatives
+
+Endless other syntaxes are thinkable.
+If we find one more pleasing or conflict with other ideas, we should adapt it.
+
+
+## Unresolved questions
+[Unresolved questions]: #unresolved-questions
+
+Nothing so far.