* doc(host) Fix the `Externals` example
The example is missing two things:
* `index` is computed but not used,
* `check_signature` is never used.
This patch tries to fix that.
* doc(host) Fix `check_signature` example
* add default-enabled std feature
* use parity-wasm/std feature only if std is enabled
* drop dependency on std::io
* use hashmap_core instead of std::collections::HashMap
* disable std::error in no_std
* core and alloc all the things
* mention no_std in readme
* add no_std feature and use hashmap_core only on no_std
* rename the no_std feature to core
* drop dependency on byteorder/std
* simplify float impl macro
* remove some trailing whitespace
* use libm for float math in no_std
* add note about no_std panics of libm to readme
* Embed nan-preserving-float crate.
* Add no_std check to the Travis CI config
* add missing dev-dependency
* Refactor TryInto → FromRuntimeValue.
Replace `TryInto<T, E>` with `FromRuntimeValue`.
The main difference is that `FromRuntimeValue` is implemented for the concrete type of the value we create, rather than on `RuntimeValue`. This makes more sense to me and seems more clear.
The `try_into` method is now implemented on `RuntimeValue` itself.
And finally, `FromRuntimeValue` has been made public.
* Impl AsRef<[RuntimeValue]> for RuntimeArgs
This impl can be used as an escape hatch if the user wants to use the inner slice.
* Little doc fixes for RuntimeArgs.
* Get rid of Stack error
* Add UnexpectedSignature error and remove Value err
* Publish FuncInstance::invoke
* Rename Trap to TrapKind
* Replace Trap with struct. Enum is now TrapKind
* Fixes
* Update value.rs
* Avoid reversing parameter types iter.
* Add impl From<TrapKind> for Trap
* Remove redundant clone in prepare_function_args.
* Use .into() to convert TrapKind into Trap
* Introduce Trap struct.
* get_local can't fail.
* Add MemoryOutOfBounds trap.
* from_little_endian use slice instead of vec.
* MemoryAccessOutOfBounds for mem get and set.
* from_little_endian conversion can't fail.
* call_indirect traps.
* DivisionByZero and InvalidConversionToInt
* Use traps in value to convey an error
* select: int condition on stack top
* if: int condition on stack top
* Assert pops.
* Another protions of assert pops
* Introduce ValueStack
Also, hide FunctionContext and remove some stale code
* Traps in execution
* Make it compile.
* Check args before invoke.
* Document RuntimeArgs.
* Update host.rs
* Add rustdoc for Trap.