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CONTRIBUTING.md

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+Your patches to perl6/doc are very welcome.
+
+They are even more welcome if you stick to our style and formatting
+guidelines.
+
+## General principles
+
+* Please use the present tense.
+* Link to external resources (like Wikipedia) for topics that are not
+  directly related to Perl 6 (like the math that our routines implement)
+* Duplicate small pieces of information rather than rely on linking
+* Be explicit about routine signatures. If a method accepts a `*%args`,
+  but treats some of them special, list them separately.
+
+## Documenting types
+
+Types should be documented like this (the tool `util/new-type.p6` can create
+the skeleton for you):
+
+    =TITLE role MyFunnyRole
+
+    =SUBTITLE Sentence or half-sentence about what it does
+
+        role MyFunnyRole does OtherRole is SuperClass { ... }
+
+    Longer description here about what this type is, and
+    how you can use it.
+
+        # usage example goes here
+
+    =head1 Methods
+
+    =head2 method do-it
+
+        method do-it(Int $how-often) returns Nil:D
+
+    Method description here
+
+        MyFunnyRole.do-it(2);   # example output
+
+
+When documeting a pair of a sub and a method which both do the same thing,
+the heading should be `=head2 routine do-it`, and the next thing should be two
+or more lines with the signatures. Other allowed words instead of `method`
+are `sub`, `trait`, `infix`, `prefix`, `postfix`, `circumfix`,
+`postcircumfix`, `term`.