Crate persistant_macros 

The compile-time SQL macro behind persistant::sql! (feature sql-macros of the persistant crate). A proc-macro crate cannot be extended, only wrapped, so this is PersistAnt’s own thin wrapper over unisql-macro-core; see docs/COMPILE-TIME-SQL.md.

const FIND: persistant::Sql = persistant::sql!(
    source = postgres, targets = [postgres, sqlite, mysql],
    "SELECT id, email FROM users WHERE id = $1"
);

Arguments, in any order, then the statement as the last argument (a string literal): source (required), targets (required, at least one), allow, requires, forbids, and crate = path (where the expansion finds Query, default ::persistant::embed). The statement is parsed in the source dialect and translated for every named target at build time; whatever cannot be is a compile error. Nothing is looked up in a database and no schema is read yet (the catalog-based checks are a later stage).

Macros

sql

Check and translate a literal statement at build time. See the crate documentation.

Derive Macros

FromRow

Derive FromRow for a struct with named fields, each of a type the crate can read from a cell (i64, i32, f64, bool, String, Vec<u8>, or Option of those). The struct is then read from a result row by position, and sql!(as T, ..) can check a SELECT against it at build time. #[persistant(crate = path)] names the crate the impl refers to (default ::persistant::relational).