use default type parameter instead of newtype

Dependencies

• [2] FREPDP7B add simple parametric rc impl
• [3] NW4S4ZCC rename MutTxn to GenericMutTxn
• [4] YDHYZA77 Adding the RootPage trait to access the raw bytes of a root page (needed in libpijul)
• [5] W2MIZD5B Single file databases + CRC for the root pages (checking the other pages makes everything very slow)
• [6] OP6SVMOD Resetting history
• [7] YWFYZNLZ Cleanup + inter-process concurrency
• [8] ECPAFJSB add env_borrow for Txn and MutTxn
• [9] WS4ZQM4R Debugging, tests, etc.
• [10] E4MD6T3L Proofreading and commenting of this crate (massive bug fixes included)
• [11] TJ2R4HAZ Accessing the root pages (unsafely, of course)
• [12] EDTFMMZW add dummy RcEntry trait for rc tree key
• [13] FFERM7K5 add type alias with default rc impl
• [14] SO25TWFL A few features for integrating it into Pijul
• [15] YXKP4AIW New file locks, with multiple sets of free pages
• [16] KMT3MF5N Drop a database
• [17] YATBB4O7 run cargo fmt

Change contents

• replacement in "sanakirja/src/lib.rs" at line 107
  [3.2997]→[3.0:82](∅→∅)
  − pub use environment::{Commit, Env, GenericMutTxn, MutTxn, RootDb, RootPage, Txn};
  [3.2997]

  [3.2267]
  + pub use environment::{Commit, Env, MutTxn, RootDb, RootPage, Txn};
• replacement in "sanakirja/src/environment/muttxn.rs" at line 5
  [3.80263]→[3.0:81](∅→∅)
  − impl<E: Borrow<Env>, T, R: RcEntry> std::fmt::Debug for GenericMutTxn<E, T, R> {
  [3.80263]

  [3.37172]
  + impl<E: Borrow<Env>, T, R: RcEntry> std::fmt::Debug for MutTxn<E, T, R> {
• edit in "sanakirja/src/environment/muttxn.rs" at line 32
  [2.413]→[2.413:531](∅→∅),[3.107]→[3.37287:37288](∅→∅),[3.119]→[3.37287:37288](∅→∅),[3.147]→[3.37287:37288](∅→∅),[2.531]→[3.37287:37288](∅→∅),[3.37287]→[3.37287:37288](∅→∅)
  − /// A mutable transaction using 12 bits for the reference counting.

  − pub type MutTxn<E, T> = GenericMutTxn<E, T, u64>;

  −
• replacement in "sanakirja/src/environment/muttxn.rs" at line 33
  [3.80290]→[3.108:166](∅→∅)
  − pub struct GenericMutTxn<E: Borrow<Env>, T, R: RcEntry> {
  [3.80290]

  [3.2751]
  + pub struct MutTxn<E: Borrow<Env>, T, R: RcEntry = u64> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 72
  [3.80903]→[3.167:228](∅→∅)
  − impl<E: Borrow<Env>, T, R: RcEntry> GenericMutTxn<E, T, R> {
  [3.80903]

  [3.2393]
  + impl<E: Borrow<Env>, T, R: RcEntry> MutTxn<E, T, R> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 81
  [3.7735]→[3.229:299](∅→∅)
  − impl<E: Borrow<Env>, T, R: RcEntry> Drop for GenericMutTxn<E, T, R> {
  [3.7735]

  [3.80962]
  + impl<E: Borrow<Env>, T, R: RcEntry> Drop for MutTxn<E, T, R> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 103
  [3.8146]→[2.532:641](∅→∅)
  − impl<'a, E: Borrow<Env>, T, R: RcEntry> Commit

  − for GenericMutTxn<E, &'a mut GenericMutTxn<E, T, R>, R>

  − {
  [3.8146]

  [3.37309]
  + impl<'a, E: Borrow<Env>, T, R: RcEntry> Commit for MutTxn<E, &'a mut MutTxn<E, T, R>, R> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 168
  [3.82078]→[2.642:697](∅→∅)
  − pub fn mut_txn_begin<E: Borrow<Self>, R: RcEntry>(
  [3.82078]

  [2.697]
  + pub fn mut_txn_begin<E: Borrow<Self>>(env: E) -> Result<MutTxn<E, ()>, Error> {

  + Self::mut_txn_begin_generic_rc(env)

  + }

  +

  + /// Start a mutable transaction. Mutable transactions that go out

  + /// of scope are automatically aborted.

  + pub fn mut_txn_begin_generic_rc<E: Borrow<Self>, R: RcEntry>(
• replacement in "sanakirja/src/environment/muttxn.rs" at line 176
  [2.713]→[2.713:763](∅→∅)
  − ) -> Result<GenericMutTxn<E, (), R>, Error> {
  [2.713]

  [3.82162]
  + ) -> Result<MutTxn<E, (), R>, Error> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 207
  [3.10473]→[3.513:544](∅→∅)
  − Ok(GenericMutTxn {
  [3.10473]

  [3.83562]
  + Ok(MutTxn {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 241
  [3.3232]→[3.545:615](∅→∅)
  − impl<E: Borrow<Env>, R: RcEntry> Commit for GenericMutTxn<E, (), R> {
  [3.3232]

  [3.84119]
  + impl<E: Borrow<Env>, R: RcEntry> Commit for MutTxn<E, (), R> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 365
  [3.86004]→[3.616:677](∅→∅)
  − impl<E: Borrow<Env>, T, R: RcEntry> GenericMutTxn<E, T, R> {
  [3.86004]

  [3.15482]
  + impl<E: Borrow<Env>, T, R: RcEntry> MutTxn<E, T, R> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 476
  [3.87011]→[3.678:769](∅→∅)
  − impl<E: Borrow<Env>, T, R: RcEntry> sanakirja_core::AllocPage for GenericMutTxn<E, T, R> {
  [3.87011]

  [3.87091]
  + impl<E: Borrow<Env>, T, R: RcEntry> sanakirja_core::AllocPage for MutTxn<E, T, R> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 559
  [3.19838]→[3.770:831](∅→∅)
  − impl<E: Borrow<Env>, A, R: RcEntry> GenericMutTxn<E, A, R> {
  [3.19838]

  [3.19877]
  + impl<E: Borrow<Env>, A, R: RcEntry> MutTxn<E, A, R> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 624
  [3.90733]→[3.832:922](∅→∅)
  − impl<E: Borrow<Env>, A, R: RcEntry> sanakirja_core::LoadPage for GenericMutTxn<E, A, R> {
  [3.90733]

  [3.20953]
  + impl<E: Borrow<Env>, A, R: RcEntry> sanakirja_core::LoadPage for MutTxn<E, A, R> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 649
  [3.4392]→[3.923:997](∅→∅)
  − impl<E: Borrow<Env>, T, R: RcEntry> RootPage for GenericMutTxn<E, T, R> {
  [3.4392]

  [3.120]
  + impl<E: Borrow<Env>, T, R: RcEntry> RootPage for MutTxn<E, T, R> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 658
  [3.367]→[3.998:1059](∅→∅)
  − impl<E: Borrow<Env>, T, R: RcEntry> GenericMutTxn<E, T, R> {
  [3.367]

  [3.21017]
  + impl<E: Borrow<Env>, T, R: RcEntry> MutTxn<E, T, R> {
• replacement in "sanakirja/src/environment/muttxn.rs" at line 684
  [3.21349]→[3.1060:1132](∅→∅)
  − impl<E: Borrow<Env>, T, R: RcEntry> RootDb for GenericMutTxn<E, T, R> {
  [3.21349]

  [3.21399]
  + impl<E: Borrow<Env>, T, R: RcEntry> RootDb for MutTxn<E, T, R> {