0.052  2025-01-29
  [Requirement Changes]
    * Require SPVM 0.990042.
  [Test Improvement]
    * Call Fn#destroy_runtime_permanent_vars method in the end of tests.
0.051  2025-01-16
  [Internal Changes]
    * Update .gitignore and MANIFEST.SKIP.
    * Compile sources by GNU C99 instead of C99.
    * Change source file names not to conflict them.
  [Exception Changes]
    * Unicode#uchar method throws an exception if $offset_ref is not defined.
  [New Features]
    * Add version.
  [Requirement Changes]
    * Require SPVM 0.990038.
    
0.05  2023-04-04
  [License Change]
    * The license is changed to MIT License.
  [Prerequirement Change]
    * SPVM 0.9701 is required.
0.04  2022-06-21
  [Internal Compatible Changes]
    * Use SPVM::ExchangeAPI method instead of SPVM functions.
0.03  2022-06-21

  - Catch up with SPVM 0.9610.
  
0.02  2022-06-13

  - Catch up with latest SPVM.
  
0.01  2022-06-07

  - First development release