υλ

υλ(pronounced weird lambda) is a esolang created by User:Yayimhere based on lambda calculus. its very weird

commands and semantics

fundamentally υλ is built on lambda calculus, but is in practice quite different. and no a normal lambda function is not valid

!x.y create a lambda function with body y and with input x. this expression cannot by itself be applied to anything, only be fed into other functions(in which it then transforms to acting like a normal lambda with no restrictions).

any binary number written down, corresponds to the church numeral of the same value.

f;x => y will modify the function f such that if it ever in any reduction step has a subexpression(which may in size from a single function to the whole expression) equal to x(ignoring abstraction names, i.e theres no difference between !x. x x and !y.y y), it will be replaced with y.

y .x applies function y to input x. With multiple inputs, it would be y .x.z.w ect ect, with x being the first input, and w being the last.

[...] functions like normal brackets, with the contents inside being executed before the ones outside.