cons_expr

About cons_expr

cons_expr is:

• Scheme-inspired
  • scheme syntax and features
  • does not support pairs or macros
  • any value once captured is const
  • any redefinition of a value shadows the previous value
• Constexpr-capable
  • cons_expr::cons_expr is constinit meaning that it is always 0-cost to construct a cons_expr interpreter
  • Any script can be executed at compile time.
  • Why execute script at compile time?
    • I don't know your other use cases
    • But you can use this feature to set up your entire scripting environment at compile time, then execute scripts at runtime
• Simple and small
  • I'm attempting to keep the code as compact as possible. As of now it is "feature complete." Any additional features will go as add-ons in the "utility" header
  • I'm not happy with the fix_identifiers family of functions. They need to be simplified and made better.
  • Compilation of entire engine is just a few seconds, even with optimizations.
• Easy to use
  • Include one header and go! See examples.
• Embeddable scripting language
  • Bi-directional support for functions between script and C++.
  • All supported types must be known at compile time.
• For C++23
  • Currently only known to work with GCC 13.1.

Command Line Inspection Tool

ccons_expr can be used to execute scripts and inspect the state of the runtime system live

Important Notes

• Objects are never destroyed, but because they are treated as immutable, they are reused as much as possible.
• All types contained in the script are required to be trivial
• If you expand beyond the statically allocated storage, dynamic storage is utilized. If you maintain dynamic storage from compile-time to run-time, you will get a compile time error.