Trait MapConstraintExt 

pub trait MapConstraintExt<T> {
    // Required method
    fn map_constraint(
        self,
        map: &ConstraintMap,
        data: &Value,
        url: impl Into<String>,
    ) -> Result<T, ActionError>;
}

Extension trait on Result<T, DbErr> for ergonomic call-site mapping.

Eliminates closure ladders at the write site: instead of chaining .map_err(|e| map.try_map(e).map(...).unwrap_or_else(...)), use:

let page = new_page.insert(db).await
    .map_constraint(&map, &data, "/pages/new")?;

On a matching UNIQUE violation the ValidationError is flashed into the session and an crate::http::action::ActionError configured to redirect to url is returned (identical to the Phase 190 surfacing chain).

On any non-matching error, From<DbErr> for ActionError is applied — the existing passthrough — so no error is ever swallowed.

Required Methods

fn map_constraint( self, map: &ConstraintMap, data: &Value, url: impl Into<String>, ) -> Result<T, ActionError>

Map a DB UNIQUE-constraint violation to a field-level error and redirect.

See the trait documentation for full semantics.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl<T> MapConstraintExt<T> for Result<T, DbErr>

fn map_constraint( self, map: &ConstraintMap, data: &Value, url: impl Into<String>, ) -> Result<T, ActionError>

Implementors