officially support #![no_std] #41 -- WIP

CHANGELOG.md

@@ -14,6 +14,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 ### Fixed
 - use full path for result #39
 - support `#[deny(missing_docs)]` #37
+- support `#![no_std]` #41
 
 ## [0.3.0] - 2017-02-05
 

src/lib.rs

@@ -379,10 +379,18 @@ fn builder_for_struct(ast: syn::MacroInput) -> quote::Tokens {
             SetterPattern::Mutable => quote!(&self),
             SetterPattern::Immutable => quote!(&self),
         };
+        let initializers_ref = &initializers;
         quote!(
+            #[cfg(not(no_std))]
             #builder_vis fn build(#ref_self) -> ::std::result::Result<#struct_name #ty_generics, ::std::string::String> {
                 Ok(#struct_name {
-                    #(#initializers)*
+                    #(#initializers_ref)*
+                })
+            }
+            #[cfg(no_std)]
+            #builder_vis fn build(#ref_self) -> ::core::result::Result<#struct_name #ty_generics, ::collections::string::String> {
+                Ok(#struct_name {
+                    #(#initializers_ref)*
                 })
             }
         )

tests/no_std.rs

@@ -0,0 +1,20 @@
+#![no_std]
+#![feature(collections)]
+#![allow(dead_code)]
+
+#[macro_use]
+extern crate derive_builder;
+extern crate collections;
+
+#[derive(Builder)]
+struct IgnoreEmptyStruct {}
+
+#[test]
+fn empty_struct() {
+    // this is just a compile-test - no run time checks required.
+}
+
+#[test]
+fn write_docs() {
+    unimplemented!()
+}