Changes between Version 4 and Version 5 of SoC2016

Timestamp:

Jan 11, 2016, 9:44:28 AM (7 years ago)

Author:

Niall Douglas

Comment:

slight improvements to project idea

SoC2016

@@ -138 +138 @@
 ==== Programming competency test ====
 Write a function which uses one of the compile time string hashing techniques at https://stackoverflow.com/questions/2111667/compile-time-string-hashing
-to generate a constexpr `std::array<unsigned>` of its input strings. The function ought to have the following
+(or a constexpr hash function of your preference) to generate a constexpr `std::array<unsigned>` of its input strings. The function ought to have the following
 prototype:
 
@@ -145 +145 @@
 template<class... Strings> constexpr std::array<unsigned, sizeof...(Strings)> hash_strings(Strings&&... strings);
 
-// Example of usage
-constexpr std::array<unsigned, 4> string_hashes = hash_strings("google", "summer", "of", "code");
+// Examples of usage
+constexpr std::array<unsigned, 0> string_hashes0 = hash_strings();
+constexpr std::array<unsigned, 2> string_hashes2 = hash_strings("niall", "douglas");
+constexpr std::array<unsigned, 4> string_hashes4 = hash_strings("google", "summer", "of", "code");
+// This should fail elegantly and usefully ...
+//constexpr std::array<unsigned, 0> string_hashes_fail = hash_strings(5);
 }}}
+
+In your submission you should:
+
+1. Explain why you chose the constexpr string hash function you did and the strengths of your choice over other choices.
+2. Test that the output is identical whether executed by the compiler at compile time, or at runtime.
+3. '''Prove''' that the compile time constexpr implementation generates no runtime code whatsoever.
 
 Submission of the programming test should be via copying and pasting the code you wrote into the end of the proposal you submit to Google Melange.