Tentatively derive pest::Parser normally

If it still creates spurious recompilations, I'll revert that

1 files changed, 6 insertions, 1 deletions

diff --git a/dhall_generated_parser/src/lib.rs b/dhall_generated_parser/src/lib.rs
index 280b75e..fbb9ccd 100644
--- a/dhall_generated_parser/src/lib.rs
+++ b/dhall_generated_parser/src/lib.rs
@@ -14,4 +14,9 @@
 // additional overrides are done in ../build.rs.
 // The lines that are commented out in ./dhall.pest.visibility are marked as
 // silent (see pest docs for what that means) in the generated pest file.
-include!(concat!(env!("OUT_DIR"), "/grammar.rs"));
+
+use pest_derive::Parser;
+
+#[derive(Parser)]
+#[grammar = "dhall.pest"]
+pub struct DhallParser;