forked from extern/nushell
34 lines
853 B
Rust
34 lines
853 B
Rust
use nu_protocol::Value;
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use std::collections::HashSet;
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pub fn get_columns<'a>(input: impl IntoIterator<Item = &'a Value>) -> Vec<String> {
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let mut columns = vec![];
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for item in input {
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if let Value::Record { cols, vals: _, .. } = item {
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for col in cols {
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if !columns.contains(col) {
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columns.push(col.to_string());
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}
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}
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} else {
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return vec![];
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}
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}
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columns
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}
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// If a column doesn't exist in the input, return it.
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pub fn nonexistent_column(inputs: Vec<String>, columns: Vec<String>) -> Option<String> {
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let set: HashSet<String> = HashSet::from_iter(columns.iter().cloned());
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for input in &inputs {
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if set.contains(input) {
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continue;
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}
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return Some(input.clone());
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}
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None
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}
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