X-Git-Url: https://git.ralfj.de/rust-101.git/blobdiff_plain/4f61be32dd480f23a7fef05ee66c42ae27c980c6..934a02211cd612a968195ded4bcc92e175dc0aff:/src/part01.rs diff --git a/src/part01.rs b/src/part01.rs index ed4f73f..56272b2 100644 --- a/src/part01.rs +++ b/src/part01.rs @@ -16,7 +16,7 @@ fn sqr(i: i32) -> i32 { i * i } //@ So we can just write `i * i`, the expression that returns the square if `i`! //@ This is very close to how mathematicians write down functions (but with more types). -// Conditionals are also just expressions. You can compare this to the ternary `? :` operator +// Conditionals are also just expressions. This is comparable to the ternary `? :` operator // from languages like C. fn abs(i: i32) -> i32 { if i >= 0 { i } else { -i } } @@ -35,11 +35,17 @@ fn number_or_default(n: NumberOrNothing, default: i32) -> i32 { } } +// It is even the case that blocks are expressions, evaluating to the last expression they contain. +fn compute_stuff(x: i32) -> i32 { + let y = { let z = x*x; z + 14 }; + y*y +} + // Let us now refactor `vec_min`. fn vec_min(v: Vec) -> NumberOrNothing { //@ Remember that helper function `min_i32`? Rust allows us to define such helper functions *inside* other //@ functions. This is just a matter of namespacing, the inner function has no access to the data of the outer - //@ one. Still, being able to nicely group functions can be very useful. + //@ one. Still, being able to nicely group functions can significantly increase readability. fn min_i32(a: i32, b: i32) -> i32 { if a < b { a } else { b } /*@*/ } @@ -96,8 +102,8 @@ pub fn main() { // You will have to replace `part00` by `part01` in the `main` function in // `main.rs` to run this code. -// **Exercise 01.1**: Write a funtion `vec_sum` that computes the sum of all values of a `Vec`. +// **Exercise 01.1**: Write a function `vec_sum` that computes the sum of all values of a `Vec`. // **Exercise 01.2**: Write a function `vec_print` that takes a vector and prints all its elements. -//@ [index](main.html) | [previous](part00.html) | [next](part02.html) +//@ [index](main.html) | [previous](part00.html) | [raw source](workspace/src/part01.rs) | [next](part02.html)