Trait HasFieldMap

pub(crate) trait HasFieldMap {
    // Required method
    fn get_field_binding(&self, field: &String) -> Option<&TokenStream>;

    // Provided method
    fn build_format(&self, input: &str, span: Span) -> TokenStream { ... }
}

Required Methods

fn get_field_binding(&self, field: &String) -> Option<&TokenStream>

Returns the binding for the field with the given name, if it exists on the type.

Provided Methods

fn build_format(&self, input: &str, span: Span) -> TokenStream

In the strings in the attributes supplied to this macro, we want callers to be able to reference fields in the format string. For example:

/// Suggest `==` when users wrote `===`.
#[suggestion(slug = "parser-not-javascript-eq", code = "{lhs} == {rhs}")]
struct NotJavaScriptEq {
    #[primary_span]
    span: Span,
    lhs: Ident,
    rhs: Ident,
}

We want to automatically pick up that {lhs} refers self.lhs and {rhs} refers to self.rhs, then generate this call to format!:

format!("{lhs} == {rhs}", lhs = self.lhs, rhs = self.rhs)

This function builds the entire call to format!.

Implementors

impl HasFieldMap for DiagnosticDeriveVariantBuilder

impl<'parent, 'a> HasFieldMap for SubdiagnosticDeriveVariantBuilder<'parent, 'a>