test SFINAE variants

#test

test-files/golden-tests/metadata/sfinae.adoc

@@ -0,0 +1,354 @@
+= Reference
+:mrdocs:
+
+[#index]
+== Global namespace
+
+
+=== Types
+
+[cols=2]
+|===
+| Name | Description 
+
+| <<A-09,`A`>> 
+| The partial specialization of A is enabled via a template parameter
+
+
+
+| <<A-02,`A&lt;T, void&gt;`>> 
+| Specialization for floating point types
+
+
+
+|===
+=== Functions
+
+[cols=2]
+|===
+| Name | Description 
+
+| <<f1,`f1`>> 
+| Enabled via return type
+
+
+
+| <<f10,`f10`>> 
+| Enabled via type template parameter
+
+
+
+| <<f2,`f2`>> 
+| Enabling a specified return type
+
+
+
+| <<f3,`f3`>> 
+| Enabling a specified return type in another namespace
+
+
+
+| <<f4,`f4`>> 
+| Enabled via return type with std&colon;&colon;enable&lowbar;if
+
+
+
+| <<f5,`f5`>> 
+| Enabled via a non&hyphen;type template parameter with helper
+
+
+
+| <<f6,`f6`>> 
+| Enabled via a non&hyphen;type template parameter without helper
+
+
+
+| <<f7,`f7`>> 
+| Enabled via a non&hyphen;type template parameter using int instead of bool
+
+
+
+| <<f8,`f8`>> 
+| Enabled via parameter without helper
+
+
+
+| <<f9,`f9`>> 
+| Enabled via parameter with helper
+
+
+
+|===
+
+[#A-09]
+== A
+
+
+The partial specialization of A is enabled via a template parameter
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;
+    class T,
+    class Enable = void&gt;
+class A;
+----
+
+
+
+
+[#A-02]
+== A&lt;T, void&gt;
+
+
+Specialization for floating point types
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;class T&gt;
+class <<A-09,A>>&lt;T, void&gt;;
+----
+
+
+
+
+[#f1]
+== f1
+
+
+Enabled via return type
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;class T&gt;
+T
+f1(T value);
+----
+
+[#f10]
+== f10
+
+
+Enabled via type template parameter
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;
+    class T,
+    typename = void&gt;
+void
+f10(T* t);
+----
+
+=== Description
+
+
+This pattern should not be used because the function signature is unmodified and therefore only supports one overload&period;
+
+It&apos;s a common mistake is to declare two function templates that differ only in their default template arguments&period;
+
+This does not work because the declarations are treated as redeclarations of the same function template (default template arguments are not accounted for in function template equivalence)&period;
+
+
+
+[#f2]
+== f2
+
+
+Enabling a specified return type
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;class T&gt;
+int
+f2(T value);
+----
+
+[#f3]
+== f3
+
+
+Enabling a specified return type in another namespace
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;class T&gt;
+std::size&lowbar;t
+f3(T value);
+----
+
+[#f4]
+== f4
+
+
+Enabled via return type with std&colon;&colon;enable&lowbar;if
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;class T&gt;
+T
+f4(T value);
+----
+
+[#f5]
+== f5
+
+
+Enabled via a non&hyphen;type template parameter with helper
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;
+    class T,
+    bool = true&gt;
+T
+f5(T value);
+----
+
+[#f6]
+== f6
+
+
+Enabled via a non&hyphen;type template parameter without helper
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;
+    class T,
+    bool = true&gt;
+T
+f6(T value);
+----
+
+[#f7]
+== f7
+
+
+Enabled via a non&hyphen;type template parameter using int instead of bool
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;
+    class T,
+    int = 0&gt;
+void
+f7(T value);
+----
+
+[#f8]
+== f8
+
+
+Enabled via parameter without helper
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;class T&gt;
+T
+f8(
+    T value,
+    void* = 0);
+----
+
+[#f9]
+== f9
+
+
+Enabled via parameter with helper
+
+
+
+=== Synopsis
+
+
+Declared in `&lt;sfinae&period;cpp&gt;`
+
+[source,cpp,subs="verbatim,replacements,macros,-callouts"]
+----
+template&lt;class T&gt;
+T
+f9(
+    T value,
+    void* = 0);
+----
+
+
+
+[.small]#Created with https://www.mrdocs.com[MrDocs]#