Struct RewriteAssignment 

pub struct RewriteAssignment {
    pub pointer: String,
    pub column: String,
    pub ir: IrExpr,
    pub sql: String,
    pub reads_a_multi_link: bool,
}

Compile a schema Trigger’s handler PyQL statement for DDL emission — same shape as compile_fn_body, but instead of fn_params this binds __new__/__old__ as the inserted/updated/deleted row (see Compiler::special_anchors’s own doc comment), gated by on_mask (Pylon’s On bitmask: 1=Insert, 2=Update, 4=Delete): __old__ is bound whenever on_mask does not include Insert (so Update-only, Delete-only, and Update+Delete all get it — but never a mask that includes Insert, even combined with Update, since a shared trigger function has no old row on the Insert branch of that combination); __new__ is bound whenever on_mask does not include Delete, by the mirror-image argument. A mask combining Insert and Delete (with no Update) legally binds neither. Referencing an anchor that isn’t bound is a compile error, not a runtime NULL. One compiled rewrite: the column it writes and the value it writes there.

Fields

pointer: String

column: String

ir: IrExpr

sql: String

reads_a_multi_link: bool

True when the expression reads one of the owner’s multi-links. Those rows live in a junction table the statement writes after the row itself, so a BEFORE trigger reading one sums an empty set — see export::rewrite_trigger_infos.