Skip to content

notes.md

Latest commit

 

History

History
93 lines (83 loc) · 4.49 KB

notes.md

File metadata and controls

93 lines (83 loc) · 4.49 KB

Notes

  • Avoid returning Option from combinators where possible.
    • Instead, combinators should add .optional() to dependent combinators.
    • This way there's no guessing whether the combinator returns a required value or not.
    • There are exceptions, where None is represented by tokens, like NULL or NONE.
      • Examples include string_or_null, and right_type.
  • Where a Vec can be empty, use Option<Vec>.
    • A lot of productions return non-empty Vecs, so Option makes it clearer when Vecs can be empty.
    • Option<Vec> has no overhead.
  • Don't implement these. They're just Rust's String/Vec:
    • common/stringinfo.c / include/lib/stringinfo.h
    • backend/utils/mb/stringinfo_mb.c / include/mb/stringinfo_mb.h
  • Check layout of structs and enums with #![feature(rustc_attrs)] + #[rustc_layout(debug)].
  • Use test_matrix instead of test_case.
    • Even though test_matrix has advanced features, it can still be used as a replacement for test_case.
    • RustRover doesn't detect the syntax of test_case, likely from a conflict with std's macro of the same name.
    • RustRover can also detect the syntax of test_matrix, so there'll be no complaints about unused imports.
  • indirection and opt_indirection functions:
    • check_func_name: only allows ( '.' col_label )[1..] == ( attrs )[1..]
    • check_indirection: * is only allowed as the last item
    • makeColumnRef:
      • splits the name (.) from subscripts ([])
      • * is only allowed as the last item of the whole source list, if there are no indexes.
      • * is allowed in any position after an index, and can show up multiple times.
      • examples:
        • x -> (["x"], [])
        • x.y -> (["x", "y"], [])
        • x.y.* -> (["x", "y", All], [])
        • x.y[0].*.foo.bar.* -> (["x", "y"], [i(0), All, "foo", "bar", All])
        • *[foo] -> ([All], [i("foo")])
    • makeRangeVarFromQualifiedName: qualified name == ( attrs ){1, 3}
  • Combinators should use specific enums, instead of using the generic makeDefElem/DefElem from C code.

TO DO

  • Allow case-insensitive search on Mphf, specifically to search for keywords.
    • Maybe use the unicase crate?
  • Maybe change Mphf to borrow field(s) as the key.
  • Change ParserResult.result to be Vec<ParseResult<RawStmt>>.
    • Introduce a fail fast (compile time) flag.
    • In debug mode: fail fast == false, and returns all errors until EOF.
    • In release mode: fail fast == true, and returns the first error as the last element of the Vec.
    • Optional: Move warnings into ParserResult.
      • E.g.: Vec<(ParseResult<RawStmt>, Vec<ParserWarningKind>)>.
      • struct { result: ParseResult<RawStmt>, warnings: Vec<ParserWarningKind> }.
  • Wrap ParserWarningKind in a LocatedErrorReport.
  • Merge Parser.move_stmt into Parser.fetch_stmt
  • Test NumericSpec.
  • Support encodings besides UTF-8: include/mb/pg_wchar.h, common/wchar.c, etc
    • For now:
      • Assume only UTF-8;
      • If any code uses encodings, throw an error (user input), or just implicitly use UTF-8 (internally);
      • If needed, make no-op code.
  • Support i18n.
    • For now, all output will be EN.
  • Guc 1st implementation will be read-only.
    • Options to change the settings will return an error or be ignored.
    • Every object will have access to the global instance, but that will change in the future.
  • For now logging is reported via Result.
    • Later, this will be used to actually log out at certain end/finish/completion points.
  • Organize pg_ast into submodules.
  • Replace RenameStmt with <ObjectType>::Rename variant.
    • For example, RoleStmt::Rename(RenameRole), RoleStmt::Create(CreateRole), etc.
    • It won't match PG-C structures, but it'll make searching for the relevant types easier.
    • Same replacement for AlterOwnerStmt.
    • See DatabaseStmt for a (clunky) example of this.
    • Generically, search for these enums: enum\s+\w+Target\b - and filter for the ones that are list of object type.

Build C Postgres

pacman -S flex bison icu-devel

mkdir pg_build
cd pg_build

time ../postgres/configure ICU_CFLAGS='-I/usr/include' ICU_LIBS='-L/usr/lib -licui18n -licuuc -licudata' --host=x86_64-w64-mingw32 --enable-debug --enable-cassert

#time make -j $(nproc)

for f in $(find -name Makefile -exec grep -lP '^generated-headers:' {} \+ | xargs dirname) ; do
  echo $f
  (
    cd $f
    make generated-headers
  )
done

( cd ./src/backend/parser/ ; make scan.c )