mruby 2.0.1 Release Notes

We are proudly annoucing the stable release of mruby 2.0 series - mruby 2.0.1.

New Features

Core Language Features

• Support string literal concatenation.

Core Libraries

Ruby 2.6 Features

• Add Enumerator::Chain, Enumerable#chain and Enumerator#+.
• Add function composition operators << and >> to Proc and Method.

Compatibility

• Recover methods removed in mruby 2.0.0. String#to_str, Integer#to_int, Float#to_int
• Improve compatibility to CRuby for Float#to_s #4225

mruby-class-ext

• Add methods.
  Module#<, Module<=, Module>, Module>=, Module<=>

mruby-pack

• Support Big-endian platform.

Tools

mruby debugger (mrdb)

• Add info locals command.

New C APIs

mruby core

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MRB_API mrb_value mrb_ary_splice(mrb_state *mrb, mrb_value self, mrb_int head, mrb_int len, mrb_value rpl);
MRB_API void mrb_notimplement(mrb_state*);
MRB_API mrb_value mrb_vformat(mrb_state *mrb, const char *format, va_list ap);

String class

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MRB_API double mrb_cstr_to_dbl(mrb_state *mrb, const char *s, mrb_bool badcheck);
MRB_API mrb_value mrb_cstr_to_inum(mrb_state *mrb, const char *s, mrb_int base, mrb_bool badcheck);

Hash class

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MRB_API void mrb_hash_foreach(mrb_state *mrb, struct RHash *hash, mrb_hash_foreach_func *func, void *p);
MRB_API mrb_int mrb_hash_size(mrb_state *mrb, mrb_value hash);

Object class

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MRB_API void mrb_iv_foreach(mrb_state *mrb, mrb_value obj, mrb_iv_foreach_func *func, void *p);

Time class

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MRB_API mrb_time_at(mrb_state *mrb, double sec, double usec, enum mrb_timezone zone);

Reducing Memory Consumption

• Remove symbol hash table from mrb_state structure.
  Use linear search instead. Number of symbols is usually small (<1K), so we don’t need performance boost from hash tables. In our benchmark measurement, hash tables consumes 790KB for build/full-debug/mrbtest.

• Implement inline packed symbols.
  Small symbols with all alphanumeric characters (<5) are packed in 32bit symbol integer a la base64.
  This means those small symbols are not listed in Symbol.all_symbols.

Breaking Changes

There are three major breaking changes from mruby 2.0.0

Binary (MRB) format

• Change compiled binary format version. (“0005” -> “0006”)

Add RRange API

Developers must use following APIs for accessing attributes of RRange because RRange structure depends on boxing setting.

• mrb_range_beg
• mrb_range_end
• mrb_range_excl_p

Remove C API

• Functions to be made static (MRB_API was not needed):
  mrb_mod_module_function(), mrb_obj_hash(), mrb_str_len_to_inum(), sym2name_len()
• Functions to remove MRB_API from definitions (referenced from within libmruby):
  mrb_mod_cv_defined(), mrb_mod_cv_get(), mrb_f_send()

Small incompatible changes in function prototypes

• mrb_parser_get_filename: return value changed to mrb_sym.
• mrb_debug_get_filename: add mrb_state* as a first argument.
• mrb_debug_get_line: ditto.

Remove methods

• Remove Kernel#class_defined? which is not available in CRuby; #3829

Major bug fixes

• Fixed a bug on platforms without BYTE_ORDER; fix #4190
• Fix 0.0 and -0.0 handling.
• Fix dump/load float leteral evaluate to infinity.
• Fix Symbol#size for multi-byte characters with MRB_UTF8_STRING.
• Add OP_ENTER to blocks without parameters; fix #4175
• Should not check non-node value to void_expr_error; fix #4203 #4192
• Should not copy keys&values when a hash table is empty; fix #4270
• Raise error on failed comparison in sort; ref #4307
• Fix memory leak in time_update_datetime; fix #4308

Evaluated mrbgems list (NPO mruby forum)

See the list.