the trait `core::marker::Sized` is not implemented for the type `Self`

[ipconfiger]

rust version: Nightly (1.8)
OS: OSX 10.11.3 (15D21)

/Users/liming/.cargo/registry/src/github.com-88ac128001ac3a9a/codegenta-0.0.8/src/table_json.rs:17:2: 17:49 error: the trait core::marker::Sized is not implemented for the type Self [E0277]
/Users/liming/.cargo/registry/src/github.com-88ac128001ac3a9a/codegenta-0.0.8/src/table_json.rs:17 fn from_str(s: &str)->Result<Self, ParseError>;
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Users/liming/.cargo/registry/src/github.com-88ac128001ac3a9a/codegenta-0.0.8/src/table_json.rs:17:2: 17:49 help: run rustc --explain E0277 to see a detailed explanation
/Users/liming/.cargo/registry/src/github.com-88ac128001ac3a9a/codegenta-0.0.8/src/table_json.rs:17:2: 17:49 note: Self does not have a constant size known at compile-time
/Users/liming/.cargo/registry/src/github.com-88ac128001ac3a9a/codegenta-0.0.8/src/table_json.rs:17:2: 17:49 note: required by core::result::Result
error: aborting due to previous error
Could not compile codegenta.

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