0.4.26

• Update documentation to 2018 edition
• Rename span.unstable() method to span.unwrap(); this method is usable from a stable compiler but panics if called from outside of a procedural macro

0.4.25

• Disable stable shim when building with procmacro2_semver_exempt on a nightly compiler (#158)

0.4.24

• Remove semver exempt type proc_macro2::FileName in favor of PathBuf (rust-lang/rust@e5e29d1)
• Remove Send and Sync impls of semver exempt type SourceFile (#141)
• Support building semver exempt APIs on stable channel (#152)

0.4.23

• Work around compilation failures in docs.rs when proc-macro2 is used as a dependency (#147)

0.4.22

• Attempt to work around documentation not appearing on docs.rs (#145)

0.4.21

• Add support for constructing 128 bit Literal integers (#144)

0.4.20

• Provide unstable Group::span_open and span_close accessors to mirror the API in nightly (#134)

0.4.19

• FromIterator<TokenStream> for TokenStream (#130)

0.4.18

• Enable libproc_macro rich API with real spans when building on 1.29.0+ (#128)

0.4.17

• Performance optimization of impl PartialEq for Ident (#125)