On 18:11 Tue 23 Mar , Iustin Pop wrote:
I agree with the principle of correctness, but let's be honest - it's (many) orders of magnitude between ByteString and String and Text, not just a few percentage points…
I've been struggling with this problem too and it's not nice. Every time one uses the system readFile & friends (anything that doesn't read via ByteStrings), it hell slow.
Test: read a file and compute its size in chars. Input text file is ~40MB in size, has one non-ASCII char. The test might seem stupid but it is a simple one. ghc 6.12.1.
Data.ByteString.Lazy (bytestring readFile + length) - < 10 miliseconds, incorrect length (as expected).
Data.ByteString.Lazy.UTF8 (system readFile + fromString + length) - 11 seconds, correct length.
Data.Text.Lazy (system readFile + pack + length) - 26s, correct length.
String (system readfile + length) - ~1 second, correct length.
Is this a mistake? Your own report shows String & readFile being an order of magnitude faster than everything else, contrary to your earlier claim. -- Nick Bowler, Elliptic Technologies (http://www.elliptictech.com/)