40 lines
815 B
Rust
40 lines
815 B
Rust
// Check that pure functions can modify local state.
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pure fn sums_to(v: ~[int], sum: int) -> bool {
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let mut i = 0u, sum0 = 0;
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while i < v.len() {
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sum0 += v[i];
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i += 1u;
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}
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ret sum0 == sum;
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}
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pure fn sums_to_using_uniq(v: ~[int], sum: int) -> bool {
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let mut i = 0u, sum0 = ~mut 0;
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while i < v.len() {
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*sum0 += v[i];
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i += 1u;
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}
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ret *sum0 == sum;
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}
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pure fn sums_to_using_rec(v: ~[int], sum: int) -> bool {
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let mut i = 0u, sum0 = {f: 0};
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while i < v.len() {
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sum0.f += v[i];
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i += 1u;
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}
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ret sum0.f == sum;
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}
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pure fn sums_to_using_uniq_rec(v: ~[int], sum: int) -> bool {
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let mut i = 0u, sum0 = {f: ~mut 0};
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while i < v.len() {
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*sum0.f += v[i];
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i += 1u;
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}
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ret *sum0.f == sum;
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}
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fn main() {
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} |