Today I Learned

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String Interpolation With Integers And Sprintf

ReasonML’s Printf module comes with a number of functions for formatting values of various types. The sprintf function allows for string interpolation.

let red = 64;
let green = 256;
let blue = 128;
let alpha = 1;

let color =
  Printf.sprintf("rbga(%i, %i, %i, %i)", red, green, blue, alpha);


It functions the same as fprintf but instead of outputting the result to some channel, it returns a string. It enforces type checking as well — the %i is specifically for integers, so using that with a type other than an integer will result in a compilation error.

See the Printf docs for more details.

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