support discimator function

Author: balthasarschuess

rclrs-macros/src/impl.rs

@@ -33,6 +33,7 @@ fn derive_structured_parameters_struct(
         let mut constraints: Option<Expr> = None;
         let mut ignore_override = false;
         let mut discard_mismatching_prior_value = false;
+        let mut discriminate: Option<Expr> = None;
 
         for attr in &f.attrs {
             if attr.path().is_ident("param") {
@@ -52,6 +53,9 @@ fn derive_structured_parameters_struct(
                     } else if meta.path.is_ident("discard_mismatching_prior_value") {
                         discard_mismatching_prior_value = true;
                         Ok(())
+                    } else if meta.path.is_ident("discriminate") {
+                        discriminate = Some(meta.value()?.parse()?);
+                        Ok(())
                     } else {
                         let err = format!("Unknown key: {:?}", &meta.path.get_ident());
                         syn::Result::Err(syn::Error::new_spanned(meta.path, err))
@@ -72,6 +76,12 @@ fn derive_structured_parameters_struct(
             Some(expr) => quote! {#expr},
             None => quote! {""},
         };
+        let discriminate = match discriminate {
+            Some(expr) => quote! {
+                core::option::Option::Some(Box::new(#expr))
+            },
+            None => quote! {core::option::Option::None},
+        };
 
         let field_type = match &f.ty {
             syn::Type::Path(p) => {
@@ -100,6 +110,7 @@ fn derive_structured_parameters_struct(
               #constraints,
               #ignore_override,
               #discard_mismatching_prior_value,
+              #discriminate,
 
           )?,
         };
@@ -119,13 +130,14 @@ fn derive_structured_parameters_struct(
         fn declare_structured_(
           node: &rclrs::NodeState,
           name: &str,
-          default: Option<DefaultForbidden>,
-          description: impl Into<std::sync::Arc<str>>,
-          constraints: impl Into<std::sync::Arc<str>>,
+          default: core::option::Option<rclrs::structured::DefaultForbidden>,
+          description: impl core::convert::Into<std::sync::Arc<str>>,
+          constraints: impl core::convert::Into<std::sync::Arc<str>>,
           ignore_override: bool,
           discard_mismatching_prior_value: bool,
+          discriminate: core::option::Option<Box<dyn core::ops::function::FnOnce(rclrs::AvailableValues<T>) -> core::option::Option<T>>>,
         )
-          -> core::result::Result<Self, crate::DeclarationError> {
+          -> core::result::Result<Self, rclrs::DeclarationError> {
               core::result::Result::Ok(Self{ #(#args)*})
           }
 

rclrs/src/parameter/structured.rs

@@ -33,6 +33,7 @@ pub trait StructuredParameters: Sized {
         constraints: impl Into<std::sync::Arc<str>>,
         ignore_override: bool,
         discard_mismatching_prior_value: bool,
+        discriminate: Option<Box<dyn FnOnce(crate::AvailableValues<T>) -> Option<T>>>,
     ) -> core::result::Result<Self, crate::DeclarationError>
     where
         Self: StructuredParametersMeta<T>,
@@ -45,6 +46,7 @@ pub trait StructuredParameters: Sized {
             constraints,
             ignore_override,
             discard_mismatching_prior_value,
+            discriminate,
         )
     }
 }
@@ -70,6 +72,7 @@ pub trait StructuredParametersMeta<T>: Sized {
         constraints: impl Into<std::sync::Arc<str>>,
         ignore_override: bool,
         discard_mismatching_prior_value: bool,
+        discriminate: Option<Box<dyn FnOnce(crate::AvailableValues<T>) -> Option<T>>>,
     ) -> core::result::Result<Self, crate::DeclarationError>;
 }
 
@@ -83,7 +86,7 @@ impl NodeState {
     where
         T: StructuredParameters + StructuredParametersMeta<T0>,
     {
-        T::declare_structured(self, name, None, "", "", false, false)
+        T::declare_structured(self, name, None, "", "", false, false, None)
     }
 }
 
@@ -97,6 +100,7 @@ impl<T: crate::ParameterVariant> StructuredParametersMeta<T> for crate::Mandator
         constraints: impl Into<std::sync::Arc<str>>,
         ignore_override: bool,
         discard_mismatching_prior_value: bool,
+        discriminate: Option<Box<dyn FnOnce(crate::AvailableValues<T>) -> Option<T>>>,
     ) -> core::result::Result<Self, crate::DeclarationError> {
         let builder = node.declare_parameter(name);
         let builder = match default {
@@ -111,6 +115,12 @@ impl<T: crate::ParameterVariant> StructuredParametersMeta<T> for crate::Mandator
             true => builder.discard_mismatching_prior_value(),
             false => builder,
         };
+        let builder = match discriminate {
+            Some(f) => builder.discriminate(f),
+            None => builder,
+        };
+        //builder.range(range)
+
         builder
             .description(description)
             .constraints(constraints)
@@ -127,6 +137,7 @@ impl<T: crate::ParameterVariant> StructuredParametersMeta<T> for crate::ReadOnly
         constraints: impl Into<std::sync::Arc<str>>,
         ignore_override: bool,
         discard_mismatching_prior_value: bool,
+        discriminate: Option<Box<dyn FnOnce(crate::AvailableValues<T>) -> Option<T>>>,
     ) -> core::result::Result<Self, crate::DeclarationError> {
         let builder = node.declare_parameter(name);
         let builder = match default {
@@ -141,6 +152,10 @@ impl<T: crate::ParameterVariant> StructuredParametersMeta<T> for crate::ReadOnly
             true => builder.discard_mismatching_prior_value(),
             false => builder,
         };
+        let builder = match discriminate {
+            Some(f) => builder.discriminate(f),
+            None => builder,
+        };
         builder
             .description(description)
             .constraints(constraints)
@@ -157,6 +172,7 @@ impl<T: crate::ParameterVariant> StructuredParametersMeta<T> for crate::Optional
         constraints: impl Into<std::sync::Arc<str>>,
         ignore_override: bool,
         discard_mismatching_prior_value: bool,
+        discriminate: Option<Box<dyn FnOnce(crate::AvailableValues<T>) -> Option<T>>>,
     ) -> core::result::Result<Self, crate::DeclarationError> {
         let builder = node.declare_parameter(name);
         let builder = match default {
@@ -171,9 +187,10 @@ impl<T: crate::ParameterVariant> StructuredParametersMeta<T> for crate::Optional
             true => builder.discard_mismatching_prior_value(),
             false => builder,
         };
-
-        //builder.discriminate(f)
-        //builder.range(range)
+        let builder = match discriminate {
+            Some(f) => builder.discriminate(f),
+            None => builder,
+        };
 
         builder
             .description(description)