Attempt to bound type parameter with a nonexistent trait StrAllocating #66

$ rustc --version
rustc 0.13.0-nightly (62fb41c32 2014-12-23 02:41:48 +0000)

$ cargo run -- -d'localhost:1351' -u'localhost:1350'
   Compiling docopt v0.6.18 (https://github.com/docopt/docopt.rs.git#b5e9e163)
warning: using multiple versions of crate `regex`
C:\MinGW\msys\1.0\home\mattbw\.cargo\git\checkouts\docopt.rs-643e15305361a76f\ma
ster\src\lib.rs:217:1: 217:24 note: used here
C:\MinGW\msys\1.0\home\mattbw\.cargo\git\checkouts\docopt.rs-643e15305361a76f\ma
ster\src\lib.rs:217 extern crate serialize;
                    ^~~~~~~~~~~~~~~~~~~~~~~
note: crate name: regex
C:\MinGW\msys\1.0\home\mattbw\.cargo\git\checkouts\docopt.rs-643e15305361a76f\ma
ster\src\lib.rs:216:1: 216:20 note: used here
C:\MinGW\msys\1.0\home\mattbw\.cargo\git\checkouts\docopt.rs-643e15305361a76f\ma
ster\src\lib.rs:216 extern crate regex;
                    ^~~~~~~~~~~~~~~~~~~
note: crate name: regex
C:\MinGW\msys\1.0\home\mattbw\.cargo\git\checkouts\docopt.rs-643e15305361a76f\ma
ster\src\lib.rs:486:41: 486:54 error: attempt to bound type parameter with a non
existent trait `StrAllocating`
C:\MinGW\msys\1.0\home\mattbw\.cargo\git\checkouts\docopt.rs-643e15305361a76f\ma
ster\src\lib.rs:486                where I: Iterator<S>, S: StrAllocating {
                                                            ^~~~~~~~~~~~~
error: aborting due to previous error
Could not compile `docopt`.

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