Implement FromStr for Caps and Structure

gstreamer/src/caps.rs

@@ -7,6 +7,7 @@
 // except according to those terms.
 
 use std::fmt;
+use std::str;
 use miniobject::*;
 use structure::*;
 
@@ -58,6 +59,14 @@ impl GstRc<CapsRef> {
     }
 }
 
+impl str::FromStr for Caps {
+    type Err = ();
+
+    fn from_str(s: &str) -> Result<Self, ()> {
+        Caps::from_string(s).ok_or(())
+    }
+}
+
 impl CapsRef {
     pub fn set_simple(&mut self, values: &[(&str, &glib::Value)]) {
         for &(name, ref value) in values {

gstreamer/src/structure.rs

@@ -9,6 +9,7 @@
 use std::fmt;
 use std::ptr;
 use std::mem;
+use std::str;
 use std::ffi::CStr;
 use std::ops::{Deref, DerefMut};
 use std::borrow::{Borrow, ToOwned, BorrowMut};
@@ -123,6 +124,14 @@ impl PartialEq<StructureRef> for Structure {
 
 impl Eq for Structure {}
 
+impl str::FromStr for Structure {
+    type Err = ();
+
+    fn from_str(s: &str) -> Result<Self, ()> {
+        Structure::from_string(s).ok_or(())
+    }
+}
+
 impl Borrow<StructureRef> for Structure {
     fn borrow(&self) -> &StructureRef {
         unsafe { &*self.0 }