Simplify tokenstream folding

yaserde_derive/src/de/expand_struct.rs

@@ -2,7 +2,7 @@ use attribute::*;
 use de::build_default_value::build_default_value;
 use field_type::*;
 use proc_macro2::{Span, TokenStream};
-use quote::{ToTokens, TokenStreamExt};
+use quote::ToTokens;
 use std::collections::BTreeMap;
 use syn::DataStruct;
 use syn::Ident;
@@ -24,12 +24,8 @@ pub fn parse(
         None
       }
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut tokens, token| {
-      tokens.append_all(token);
-      tokens
-    });
 
   let variables: TokenStream = data_struct
     .fields
@@ -191,12 +187,8 @@ pub fn parse(
         None => None,
       }
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut sum, val| {
-      sum.append_all(val);
-      sum
-    });
 
   let field_visitors: TokenStream = data_struct
     .fields
@@ -383,12 +375,8 @@ pub fn parse(
         None => None,
       }
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut sum, val| {
-      sum.append_all(val);
-      sum
-    });
 
   let call_visitors: TokenStream = data_struct
     .fields
@@ -873,12 +861,8 @@ pub fn parse(
         None => None,
       }
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut sum, val| {
-      sum.append_all(val);
-      sum
-    });
 
   let attributes_loading: TokenStream = data_struct
     .fields
@@ -1093,12 +1077,8 @@ pub fn parse(
         _ => None,
       }
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut sum, val| {
-      sum.append_all(val);
-      sum
-    });
 
   let set_text: TokenStream = data_struct
     .fields
@@ -1173,12 +1153,8 @@ pub fn parse(
         | None => None,
       }
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut tokens, token| {
-      tokens.append_all(token);
-      tokens
-    });
 
   let struct_builder: TokenStream = data_struct
     .fields
@@ -1195,12 +1171,8 @@ pub fn parse(
         None
       }
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut tokens, token| {
-      tokens.append_all(token);
-      tokens
-    });
 
   quote! {
     use xml::reader::XmlEvent;
@@ -1316,12 +1288,8 @@ fn build_call_visitor(
         None
       }
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut tokens, token| {
-      tokens.append_all(token);
-      tokens
-    });
 
   Some(quote! {
     #label_name => {

yaserde_derive/src/ser/expand_enum.rs

@@ -1,7 +1,6 @@
 use attribute::*;
 use field_type::*;
 use proc_macro2::{Span, TokenStream};
-use quote::TokenStreamExt;
 use std::collections::BTreeMap;
 use syn::DataEnum;
 use syn::Fields;
@@ -36,7 +35,7 @@ pub fn serialize(
           }
         }),
         Fields::Named(ref fields) => {
-          let enum_fields = fields
+          let enum_fields: TokenStream = fields
             .named
             .iter()
             .map(|field| {
@@ -100,12 +99,8 @@ pub fn serialize(
                 _ => None,
               }
             })
-            .filter(|x| x.is_some())
+            .filter_map(|x| x)
-            .map(|x| x.unwrap())
+            .collect();
-            .fold(TokenStream::new(), |mut tokens, token| {
-              tokens.append_all(token);
-              tokens
-            });
 
           Some(quote! {
             &#name::#label{..} => {
@@ -210,12 +205,8 @@ pub fn serialize(
         }
       }
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut tokens, token| {
-      tokens.append_all(token);
-      tokens
-    });
 
   let add_namespaces: TokenStream = namespaces
     .iter()
@@ -224,12 +215,8 @@ pub fn serialize(
         .ns(#prefix, #namespace)
       ))
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut tokens, token| {
-      tokens.append_all(token);
-      tokens
-    });
 
   quote! {
     use xml::writer::XmlEvent;

yaserde_derive/src/ser/expand_struct.rs

@@ -1,7 +1,6 @@
 use attribute::*;
 use field_type::*;
 use proc_macro2::{Span, TokenStream};
-use quote::TokenStreamExt;
 use std::collections::BTreeMap;
 use std::string::ToString;
 use syn::DataStruct;
@@ -225,12 +224,8 @@ pub fn serialize(
         _ => None,
       }
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut tokens, token| {
-      tokens.append_all(token);
-      tokens
-    });
 
   let add_namespaces: TokenStream = namespaces
     .iter()
@@ -239,12 +234,8 @@ pub fn serialize(
         .ns(#prefix, #namespace)
       ))
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut tokens, token| {
-      tokens.append_all(token);
-      tokens
-    });
 
   let struct_inspector: TokenStream = data_struct
     .fields
@@ -417,12 +408,8 @@ pub fn serialize(
         None => None,
       }
     })
-    .filter(|x| x.is_some())
+    .filter_map(|x| x)
-    .map(|x| x.unwrap())
+    .collect();
-    .fold(TokenStream::new(), |mut tokens, token| {
-      tokens.append_all(token);
-      tokens
-    });
 
   quote! {
     use xml::writer::XmlEvent;