Trait ViewDefinitionSelectTrait

Source

pub trait ViewDefinitionSelectTrait {
    type Column: ViewDefinitionColumnTrait;
    type Select: ViewDefinitionSelectTrait;

    // Required methods
    fn column(&self) -> Option<&[Self::Column]>;
    fn select(&self) -> Option<&[Self::Select]>;
    fn for_each(&self) -> Option<&str>;
    fn for_each_or_null(&self) -> Option<&str>;
    fn repeat(&self) -> Option<Vec<&str>>;
    fn union_all(&self) -> Option<&[Self::Select]>;
}

Expand description

Trait for abstracting ViewDefinitionSelect across FHIR versions.

This trait provides version-agnostic access to select statement components, including columns, nested selects, iteration constructs, and union operations. Select statements define the structure and content of the output table.

§Associated Types

Column: The column definition type for this FHIR version
Select: Recursive select type for nested structures

§Key Features

Column Definitions: Direct column mappings from FHIRPath to output
Nested Selects: Hierarchical select structures for complex transformations
Iteration: forEach and forEachOrNull for processing collections
Union Operations: unionAll for combining multiple select results

§Examples

use helios_sof::traits::ViewDefinitionSelectTrait;

fn analyze_select<T: ViewDefinitionSelectTrait>(select: &T) {
    if let Some(columns) = select.column() {
        println!("Found {} columns", columns.len());
    }
     
    if let Some(for_each) = select.for_each() {
        println!("Iterating over: {}", for_each);
    }
     
    if let Some(union_selects) = select.union_all() {
        println!("Union with {} other selects", union_selects.len());
    }
}