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//! `LABELS` special form — mutual-recursion-capable local functions.
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use super::common::{compile_and_validate, compile_expect_error};

            

        

            

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#[test]

            

        

            

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fn labels_single_function_called_in_body() {

            

        

            

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    compile_and_validate("(labels ((square (x) (* x x))) (square 5))");

            

        

            

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}

            

        

            

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#[test]

            

        

            

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fn labels_mutually_recursive_functions() {

            

        

            

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    compile_and_validate(

            

        

            

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        "(labels ((even? (n) (if (= n 0) #t (odd? (- n 1)))) \

            

        

            

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                  (odd?  (n) (if (= n 0) #f (even? (- n 1))))) \

            

        

            

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            (even? 4))",

            

        

            

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    );

            

        

            

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}

            

        

            

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#[test]

            

        

            

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fn labels_multiple_body_forms() {

            

        

            

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    compile_and_validate("(labels ((id (x) x)) (id 1) (id 2) (id 3))");

            

        

            

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}

            

        

            

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#[test]

            

        

            

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fn labels_empty_definitions_compiles() {

            

        

            

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    compile_and_validate("(labels () 42)");

            

        

            

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}

            

        

            

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#[test]

            

        

            

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fn labels_missing_body_errors() {

            

        

            

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    let err = compile_expect_error("(labels ((f (x) x)))");

            

        

            

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    assert!(err.contains("LABELS"), "got: {err}");

            

        

            

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}

            

        

            

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#[test]

            

        

            

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fn labels_malformed_definition_errors() {

            

        

            

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    // Definition without a body — only name and params.

            

        

            

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    let err = compile_expect_error("(labels ((f (x))) (f 1))");

            

        

            

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    assert!(err.contains("LABELS"), "got: {err}");

            

        

            

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}