Macro sqlx_conditional_queries_layering::create_conditional_query_as

macro_rules! create_conditional_query_as {
    (($($macro_header:tt)*) @ $name:tt, $($conditional_part:tt)*) => { ... };
    ($name:tt, $($conditional_part:tt)*) => { ... };
}

Macro to handle query templates for the sqlx-conditional-queries library.

Examples

We need to enable macro_metavar_expr unstable feature Basic usage:

#![feature(macro_metavar_expr)]
let keehee = [Keehee::OwO, Keehee::UmU, Keehee::UwU]
    .choose(&mut rand::thread_rng())
    .cloned()
    .unwrap_or_default();

sqlx_conditional_queries_layering::create_conditional_query_as!(
    keehee_query,
    #keehee = match keehee {
        Keehee::OwO => "owo",
        Keehee::UmU => "umu",
        Keehee::UwU => "uwu"
    }
);

This will generate two macros _keehee_query and ‘feed__keehee_query’. _keehee_query is a template macro that accepts a type, a query and can also be provided with aditional sqlx-conditional-queries arguments.

You can use it as such:

keehee_query!(BigID, "DO YOUR QUERY", #hey=match {...})
    .fetch_one(&pool)
    .await;

feed_YOUR_QUERY_NAME on the other hand is a macro that should be used when you want to add more conditional queries on top of another existing query template.

feed_query_keehee_query!(
    super_duper_query,
    #oi = match something {
        Something::Oi => "dumb"
        Something::Nah => "cool"
    }
);

This effectively will generate a macros for a keehee_query with the addition of the #oi arguments. This behaviour is recursive, so you can also “feed” this already feeded query with more arguments if you find desireable to do so. You would use feed_super_duper_query for that.

Note: This macro relies on other macros from sqlx_conditional_queries.

See Also

• sqlx_conditional_queries

Although it would be nice to be able to use the query on multiple files, this unfortunately does not seem to be possible the way rust is structured. https://doc.rust-lang.org/stable/nightly-rustc/rustc_lint/builtin/static.MACRO_EXPANDED_MACRO_EXPORTS_ACCESSED_BY_ABSOLUTE_PATHS.html