50 lines
1.0 KiB
V
50 lines
1.0 KiB
V
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// An example deserializer implementation
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struct User {
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name string
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age int
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}
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fn main() {
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data := 'name=Alice\nage=18'
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user := decode<User>(data)
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println(user)
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}
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fn decode<T>(data string) T {
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mut result := T{}
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// compile-time `for` loop
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// T.fields gives an array of a field metadata type
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$for field in T.fields {
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$if field.typ is string {
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// $(string_expr) produces an identifier
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result.$(field.name) = get_string(data, field.name)
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} $else $if field.typ is int {
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result.$(field.name) = get_int(data, field.name)
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}
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}
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return result
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}
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fn get_string(data string, field_name string) string {
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for line in data.split_into_lines() {
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key_val := line.split('=')
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if key_val[0] == field_name {
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return key_val[1]
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}
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}
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return ''
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}
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fn get_int(data string, field string) int {
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return get_string(data, field).int()
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}
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// `decode<User>` generates:
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// fn decode_User(data string) User {
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// mut result := User{}
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// result.name = get_string(data, 'name')
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// result.age = get_int(data, 'age')
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// return result
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// }
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