String format macros for ZZ

Add this to your zz.toml file:

[dependencies] format = "*" [repos] format = "git://github.com/zzmodules/format"

using format

Creates a formatted string from a variety of special tokens with traditional printf style specifiers supported.

• {} - Treats argument like a struct, calling .display() for a char *
• {*} - Treats argument like a pointer to a struct, calling ->display() for a char *
• {0..9} - References argument by position. Treatment is the same as {}
• {*0..9} - References pointer argument by position. Treatment is same as {*}
• {$0..9} - References argument identifier name by position and uses it inline
• {0..9%X} - References argument by position with format. Treatment is like a limited printf

The @format::with() macro will treat struct and struct pointers specified with {}, {*}, and its variant as special input that should implement a displayable interface. Structs should simply implement a display() -> char * method like in the example below:

using format using log using string structVector{float x; float y} fn display(Vector *self) -> char *{new+64000 out = string::make(); out.format("Vector{x: %0.2f, y: %0.2f }", self->x, self->y); return out.cstr()} fn main() ->{let vec = Vector{x: 1.23, y: 2.46 }; log::info("%s", @format::with("{}", vec)); // Vector{x: 1.23, y: 2.46 }return0}

MIT