fn as_argument()

in src/bindgen/ir/function.rs [248:288]
41 lines of code
3 McCabe index (conditional complexity)

    fn as_argument(&self) -> Result<Option<FunctionArgument>, String> {
        match *self {
            syn::FnArg::Typed(syn::PatType {
                ref pat, ref ty, ..
            }) => {
                let ty = match Type::load(ty)? {
                    Some(x) => x,
                    None => return Ok(None),
                };
                let name = match **pat {
                    syn::Pat::Wild(..) => None,
                    syn::Pat::Ident(syn::PatIdent { ref ident, .. }) => {
                        if ty == Type::Primitive(super::PrimitiveType::VaList) {
                            None
                        } else {
                            Some(ident.unraw().to_string())
                        }
                    }
                    _ => {
                        return Err(format!(
                            "Parameter has an unsupported argument name: {:?}",
                            pat
                        ))
                    }
                };
                if let Type::Array(..) = ty {
                    return Err("Array as function arguments are not supported".to_owned());
                }
                Ok(Some(FunctionArgument {
                    name,
                    ty,
                    array_length: None,
                }))
            }
            syn::FnArg::Receiver(ref receiver) => Ok(Some(FunctionArgument {
                name: Some("self".to_string()),
                ty: gen_self_type(receiver)?,
                array_length: None,
            })),
        }
    }