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40 lines
1001 B
Rust
40 lines
1001 B
Rust
#![allow(dead_code)]
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fn main() {}
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#[allow(unnecessary_operation)]
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fn starts_with() {
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"".chars().next() == Some(' ');
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Some(' ') != "".chars().next();
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}
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fn chars_cmp_with_unwrap() {
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let s = String::from("foo");
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if s.chars().next().unwrap() == 'f' { // s.starts_with('f')
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// Nothing here
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}
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if s.chars().next_back().unwrap() == 'o' { // s.ends_with('o')
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// Nothing here
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}
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if s.chars().last().unwrap() == 'o' { // s.ends_with('o')
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// Nothing here
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}
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if s.chars().next().unwrap() != 'f' { // !s.starts_with('f')
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// Nothing here
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}
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if s.chars().next_back().unwrap() != 'o' { // !s.ends_with('o')
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// Nothing here
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}
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if s.chars().last().unwrap() != 'o' { // !s.ends_with('o')
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// Nothing here
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}
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}
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#[allow(unnecessary_operation)]
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fn ends_with() {
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"".chars().last() == Some(' ');
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Some(' ') != "".chars().last();
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"".chars().next_back() == Some(' ');
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Some(' ') != "".chars().next_back();
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}
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