36 lines
1.0 KiB
Rust
36 lines
1.0 KiB
Rust
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// AsRef and AsMut allow for cheap reference-to-reference conversions.
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// Read more about them at https://doc.rust-lang.org/std/convert/trait.AsRef.html
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// and https://doc.rust-lang.org/std/convert/trait.AsMut.html, respectively.
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// Obtain the number of bytes (not characters) in the given argument
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// Add the AsRef trait appropriately as a trait bound
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fn byte_counter<T>(arg: T) -> usize {
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arg.as_ref().as_bytes().len()
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}
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// Obtain the number of characters (not bytes) in the given argument
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// Add the AsRef trait appropriately as a trait bound
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fn char_counter<T>(arg: T) -> usize {
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arg.as_ref().chars().collect::<Vec<_>>().len()
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}
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fn main() {
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let s = "Café au lait";
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println!("{}", char_counter(s));
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println!("{}", byte_counter(s));
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}
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#[cfg(test)]
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mod tests {
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use super::*;
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#[test]
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fn different_counts() {
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let s = "Café au lait";
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assert_ne!(char_counter(s), byte_counter(s));
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}
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fn same_counts() {
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let s = "Cafe au lait";
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assert_eq!(char_counter(s), byte_counter(s));
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}
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}
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