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use hair::*;
use hair::cx::Cx;
use hair::cx::to_ref::ToRef;
use rustc::middle::region::{BlockRemainder, CodeExtentData};
use rustc::hir;
use syntax::ast;
impl<'tcx> Mirror<'tcx> for &'tcx hir::Block {
type Output = Block<'tcx>;
fn make_mirror<'a, 'gcx>(self, cx: &mut Cx<'a, 'gcx, 'tcx>) -> Block<'tcx> {
let stmts = mirror_stmts(cx, self.id, &*self.stmts);
Block {
extent: cx.tcx.region_maps.node_extent(self.id),
span: self.span,
stmts: stmts,
expr: self.expr.to_ref(),
}
}
}
fn mirror_stmts<'a, 'gcx, 'tcx>(cx: &mut Cx<'a, 'gcx, 'tcx>,
block_id: ast::NodeId,
stmts: &'tcx [hir::Stmt])
-> Vec<StmtRef<'tcx>> {
let mut result = vec![];
for (index, stmt) in stmts.iter().enumerate() {
match stmt.node {
hir::StmtExpr(ref expr, id) |
hir::StmtSemi(ref expr, id) => {
result.push(StmtRef::Mirror(Box::new(Stmt {
span: stmt.span,
kind: StmtKind::Expr {
scope: cx.tcx.region_maps.node_extent(id),
expr: expr.to_ref(),
},
})))
}
hir::StmtDecl(ref decl, id) => {
match decl.node {
hir::DeclItem(..) => {
}
hir::DeclLocal(ref local) => {
let remainder_extent = CodeExtentData::Remainder(BlockRemainder {
block: block_id,
first_statement_index: index as u32,
});
let remainder_extent =
cx.tcx.region_maps.lookup_code_extent(remainder_extent);
let pattern = Pattern::from_hir(cx.tcx, cx.tables(), &local.pat);
result.push(StmtRef::Mirror(Box::new(Stmt {
span: stmt.span,
kind: StmtKind::Let {
remainder_scope: remainder_extent,
init_scope: cx.tcx.region_maps.node_extent(id),
pattern: pattern,
initializer: local.init.to_ref(),
},
})));
}
}
}
}
}
return result;
}
pub fn to_expr_ref<'a, 'gcx, 'tcx>(cx: &mut Cx<'a, 'gcx, 'tcx>,
block: &'tcx hir::Block)
-> ExprRef<'tcx> {
let block_ty = cx.tables().node_id_to_type(block.id);
let (temp_lifetime, was_shrunk) = cx.tcx.region_maps.temporary_scope2(block.id);
let expr = Expr {
ty: block_ty,
temp_lifetime: temp_lifetime,
temp_lifetime_was_shrunk: was_shrunk,
span: block.span,
kind: ExprKind::Block { body: block },
};
expr.to_ref()
}