46 lines
807 B
Plaintext
46 lines
807 B
Plaintext
pub opaque type AssocList<key, value> {
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inner: List<#(key, value)>,
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}
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pub fn new() -> AssocList<key, value> {
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AssocList { inner: [] }
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}
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pub fn to_list(m: AssocList<key, value>) -> List<#(key, value)> {
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m.inner
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}
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pub fn insert(
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in m: AssocList<key, value>,
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key k: key,
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value v: value,
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) -> AssocList<key, value> {
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AssocList { inner: do_insert(m.inner, k, v) }
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}
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fn do_insert(
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elems: List<#(key, value)>,
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k: key,
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v: value,
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) -> List<#(key, value)> {
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when elems is {
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[] -> [#(k, v)]
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[#(k2, v2), ..rest] ->
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if k == k2 {
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[#(k, v), ..rest]
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} else {
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[#(k2, v2), ..do_insert(rest, k, v)]
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}
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}
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}
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fn fixture_1() {
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new()
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|> insert("foo", 42)
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|> insert("bar", 14)
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}
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test to_list_2() {
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to_list(fixture_1()) == [#("foo", 42), #("bar", 14)]
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}
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