IO#putc writes a single character without intermediate string allocation.
- Integer argument: writes byte value (mod 256)
- String argument: writes first character (UTF-8 aware when MRB_UTF8_STRING)
- Returns the argument (IO#putc) or nil (Kernel#putc, matching CRuby)
This provides ~44% memory reduction for character-by-character output
compared to printf "%c" or print ch.chr approaches.
Co-authored-by: Claude <noreply@anthropic.com>
added parentheses to to_enum call where the return value is used,
explicitly specifying :each for readability.
Co-authored-by: Claude <noreply@anthropic.com>
Implements File.join in C for better performance, replacing the Ruby
implementation with direct C string manipulation and array processing.
Uses mruby's built-in recursion detection (MRB_RECURSIVE_UNARY_P) for
cleaner and more reliable recursive array handling.
Co-authored-by: Claude <noreply@anthropic.com>
Implements File.path in C for better performance, replacing the Ruby
implementation that used kind_of? check with direct C type validation.
Co-authored-by: Claude <noreply@anthropic.com>
Implement C version of File.extname for better performance:
- Direct C string processing instead of Ruby basename + rindex
- Efficient path parsing with single pass through string
- Proper handling of edge cases (dotfiles, trailing slashes, etc.)
- Maintains full compatibility with Ruby implementation
Performance improvement:
- Eliminates Ruby method call overhead for basename/rindex
- Direct C string operations vs Ruby string methods
- Faster path processing for file extension extraction
Co-authored-by: Claude <noreply@anthropic.com>
Moved IO#ungetbyte from Ruby to C implementation to eliminate
boundary crossing overhead and avoid temporary string allocations.
Added io_unget_data helper function to handle raw data operations
efficiently.
Co-authored-by: Claude <noreply@anthropic.com>
Moved IO#<< from Ruby to C implementation to reduce boundary
crossing overhead. Maintains full compatibility with automatic
to_s conversion and proper return value for method chaining.
Co-authored-by: Claude <noreply@anthropic.com>
Moved IO#print from Ruby to C implementation to reduce boundary
crossing overhead. Maintains full compatibility with automatic
to_s conversion for all arguments.
Co-authored-by: Claude <noreply@anthropic.com>
Moved IO#puts from Ruby to C implementation to reduce boundary
crossing overhead. Maintains full compatibility including array
recursion and newline handling.
Co-authored-by: Claude <noreply@anthropic.com>
Added complete call-seq documentation for the entire mruby-io gem across
both Ruby and C implementations:
## Ruby Methods (mrblib/) - 50 methods documented:
### Kernel Module (kernel.rb):
- Backtick operator: shell command execution with output capture
- open: unified file/subprocess opening with pipe support
- p: debug output with inspect formatting and multiple argument handling
- print/puts/printf: output methods with proper formatting and separators
- gets/readline/readlines: input methods with various line handling options
### File Constants (file_constants.rb):
- FNM_* constants: file name matching flags for glob and fnmatch operations
with detailed explanations of case sensitivity, escaping, and pattern behavior
### IO Class (io.rb):
Class methods:
- IO.open: creates IO objects with automatic resource management
- IO.popen: subprocess communication with pipe handling
- IO.pipe: creates connected pipe endpoints for IPC
- IO.read: convenience method for reading entire files
Instance methods:
- Stream positioning: pos=, rewind, tell with proper seeking behavior
- Iteration: each, each_byte, each_char with enumerator support
- Output: puts, print, printf with formatting and newline handling
- Utility: hash, <<, ungetbyte with proper stream manipulation
- Global streams: STDIN/STDOUT/STDERR and $stdin/$stdout/$stderr
### File Class (file.rb):
Instance methods:
- Constructor: handles both file paths and file descriptors
- Timestamps: atime, ctime, mtime with proper Time object conversion
- Inspection: inspect method for debugging file objects
Class methods:
- Path utilities: join with cross-platform separator handling
- File iteration: foreach with block and enumerator support
- FileTest delegation: complete set of file type and existence checks
(directory?, exist?, file?, pipe?, size, socket?, symlink?, zero?)
- Path manipulation: extname for extension extraction, path for conversion
## C Methods (src/) - 25 methods documented:
### Core IO Operations (io.c):
- File descriptor management: fileno with proper error handling
- Stream state: closed?, eof?, sync/sync= for buffering control
- Process management: pid for pipe process tracking
- Resource management: close_on_exec?/close_on_exec= for FD_CLOEXEC handling
### Reading Operations:
- Character reading: getc, readchar with EOF handling differences
- Byte reading: getbyte, readbyte with integer conversion
- Buffer reading: read with length and output buffer support
- Stream manipulation: ungetc for character pushback
### System Operations:
- IO multiplexing: IO.select for monitoring multiple streams
- Constructor: IO.new for creating IO objects from file descriptors
- Stream flushing: flush for forcing output to OS
Co-authored-by: Atlassian Rovo Dev
The reason for this is to fix the following problems
- Even on non-Windows, drive letter recognition was still being handled.
- On Windows, paths starting with a slash were not expanded correctly.
- On Windows, relative paths containing drive letters behaved differently than in CRuby.
Due to reimplementation, the internal methods `File._concat_path`, `File._gethome` and `File._getwd` methods have been removed.
- The inner method `File._gethome` could be read as intending to use the `USERPROFILE` environment variable instead on Windows when the `HOME` environment variable is not available.
In reality, however, this was not the case.
- The result of `File.expand_path` should unify path separators with `/`, but it did not.
The Difference
Since Ruby1.9, the keyword arguments were emulated by Ruby using the hash
object at the bottom of the arguments. But we have gradually moved toward
keyword arguments separated from normal (positinal) arguments.
At the same time, we value compatibility, so that Ruby3.0 keyword
arguments are somewhat compromise. Basically, keyword arguments are
separated from positional arguments, except when the method does not
take any formal keyword arguments, given keyword arguments (packed
in the hash object) are considered as the last argument.
And we also allow non symbol keys in the keyword arguments. In that
case, those keys are just passed in the `**` hash (or raise
`ArgumentError` for unknown keys).
The Instruction Changes
We have changed `OP_SEND` instruction. `OP_SEND` instruction used to
take 3 operands, the register, the symbol, the number of (positional)
arguments. The meaning of the third operand has been changed. It is now
considered as `n|(nk<<4)`, where `n` is the number of positional
arguments, and `nk` is the number of keyword arguments, both occupies
4 bits in the operand.
The number `15` in both `n` and `nk` means variable sized arguments are
packed in the object. Positional arguments will be packed in the array,
and keyword arguments will be packed in the hash object. That means
arguments more than 14 values are always packed in the object.
Arguments information for other instructions (`OP_SENDB` and `OP_SUPER`)
are also changed. It works as the third operand of `OP_SEND`. the
difference between `OP_SEND` and `OP_SENDB` is just trivial. It assigns
`nil` to the block hidden arguments (right after arguments).
The instruction `OP_SENDV` and `OP_SENDVB` are removed. Those
instructions are replaced by `OP_SEND` and `OP_SENDB` respectively with
the `15` (variable sized) argument information.
Calling Convention
When calling a method, the stack elements shall be in the order of the
receiver of the method, positional arguments, keyword arguments and the
block argument. If the number of positional or keyword arugument (`n` or
`nk`) is zero, corresponding arguments will be empty. So when `n=0` and
`nk=0` the stack layout (from bottom to top) will be:
+-----------------------+
| recv | block (or nil) |
+-----------------------+
The last elements `block` should be explicitly filled before `OP_SEND`
or assigned to `nil` by `OP_SENDB` internally. In other words, the
following have exactly same behavior:
OP_SENDB clears `block` implicitly:
```
OP_SENDB reg sym 0
```
OP_SEND clears `block` implicitly:
```
OP_LOADNIL R2
OP_SEND R2 sym 0
```
When calling a method with only positional arguments (n=0..14) without
keyword arguments, the stack layout will be like following:
+--------------------------------------------+
| recv | arg1 | ... | arg_n | block (or nil) |
+--------------------------------------------+
When calling a method with arguments packed in the array (n=15) which
means argument splat (*) is used in the actual arguments, or more than
14 arguments are passed the stack layout will be like following:
+-------------------------------+
| recv | array | block (or nil) |
+-------------------------------+
The number of the actual arguments is determined by the length of the
argument array.
When keyword arguments are given (nk>0), keyword arguments are passed
between positional arguments and the block argument. For example, when
we pass one positional argument `1` and one keyword argument `a: 2`,
the stack layout will be like:
+------------------------------------+
| recv | 1 | :a | 2 | block (or nil) |
+------------------------------------+
Note that keyword arguments consume `2*nk` elements in the stack when
`nk=0..14` (unpacked).
When calling a method with keyword arguments packed in the hash object
(nk=15) which means keyword argument splat (**) is used or more than
14 keyword arguments in the actual arguments, the stack layout will
be like:
+------------------------------+
| recv | hash | block (or nil) |
+------------------------------+
Note for mruby/c
When mruby/c authors try to support new keyword arguments, they need
to handle the new meaning of the argument information operand. If they
choose not to support keyword arguments in mruby/c, it just raise
error when `nk` (taken by `(c>>4)&0xf`) is not zero. And combine
`OP_SENDV` behavior with `OP_SEND` when `n` is `15`.
If they want to support keyword arguments seriously, contact me at
<matz@ruby.or.jp> or `@yukihiro_matz`. I can help you.
```console
% for rb in `git ls-files '*/mrblib/*.rb' 'mrblib'`; do ruby30 -cw $rb > /dev/null; done
mrbgems/mruby-array-ext/mrblib/array.rb:389: warning: assigned but unused variable - ary
mrbgems/mruby-array-ext/mrblib/array.rb:663: warning: assigned but unused variable - len
mrbgems/mruby-hash-ext/mrblib/hash.rb:119: warning: possibly useless use of a variable in void context
mrbgems/mruby-hash-ext/mrblib/hash.rb:259: warning: assigned but unused variable - keys
mrbgems/mruby-io/mrblib/io.rb:229: warning: literal in condition
mrbgems/mruby-io/mrblib/io.rb:280: warning: literal in condition
mrbgems/mruby-string-ext/mrblib/string.rb:347: warning: assigned but unused variable - len
mrbgems/mruby-toplevel-ext/mrblib/toplevel.rb:2: warning: parentheses after method name is interpreted as an argument list, not a decomposed argument
```
Yukihiro "Matz" Matsumoto