drewbanas / Monkey-SPC

A monkey without a tree

Monkey-SPC

A monkey without a tree. A single pass compiler variation of the Monkey Language’s virtual machine. Implemented in C#.

Usage:

monkey.exe [ scriptFile.monk ] [ -b ]

• Arguments are optional and REPL mode is activated when they are not provided
• The -b switch enables benchmarking when running script files. The virtual machine's run time will be reported.

Minor language features added:

• Comments: single line (// ) and multi-line (/* */)
• Additional binary/infix operators
  • “... than and equal” comparisons: >=, <=
  • Bit shifts: >>, <<
  • Power and modulo, ^, %
• “exit” command for terminating the REPL or script
• Numbers within identifier names
• Additional error handling
  • Returns outside functions
  • Ignoring empty code

Noted implementation changes

• The parser is merged into the compiler
• The AST nodes are gone
• Where avoidable, hashmaps/dictionaries are not used for looking up:
  • Keywords
  • Pratt parse functions
  • Opcode operand counts and bit widths
• Syntax tree based optimization techniques are no longer applicable, so an opcode for less than has been added.
• Go “const” enums that originally contained string members are replaced with numeric enums