Macro mutation 

macro_rules! mutation {
    (@col $id:ident) => { ... };
    (@col $lit:expr) => { ... };
    (@build_write $builder:ident, $table:tt, { $($col:tt : $val:expr),* $(,)? }) => { ... };
    (delete $table:expr, $key_set:expr) => { ... };
    (insert $table:tt { $($rest:tt)* }) => { ... };
    (update $table:tt { $($rest:tt)* }) => { ... };
    (insert_or_update $table:tt { $($rest:tt)* }) => { ... };
    (replace $table:tt { $($rest:tt)* }) => { ... };
}

Constructs a Mutation using declarative syntax.

Examples

use google_cloud_spanner::key::KeySet;
use google_cloud_spanner::mutation;

// Insert operation
let insert_mut = mutation!(insert "Singers" {
    SingerId: 1_i64,
    FirstName: "Marc",
    LastName: "Richards",
});

// Update operation
let update_mut = mutation!(update "Albums" {
    SingerId: 1_i64,
    AlbumId: 1_i64,
    MarketingBudget: 100_000_i64,
});

// Insert or Update operation
let upsert_mut = mutation!(insert_or_update "Singers" {
    SingerId: 1_i64,
    FirstName: "Marc",
    LastName: "Richards",
});

// Replace operation
let replace_mut = mutation!(replace "Singers" {
    SingerId: 1_i64,
    FirstName: "Marc",
    LastName: "Richards",
});

// Delete operation
let delete_mut = mutation!(delete "Singers", KeySet::all());