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functionAssignments

Reports reassigning variables declared with function declarations.

✅ This rule is included in the ts javascript presets.

Reassigning a function declaration can make code harder to understand and maintain. Function declarations are hoisted to the top of their scope, and reassigning them can lead to unexpected behavior.

Examples

Section titled “Examples”
AEfuncti5<3 sp ansty="le--0:#82AAFF;--1:#3B61">B0calcula1<1(sp ansty="le--0:#D7DBE0;--1:#403F">53val7<2:sp ansty="le--0:#D6DEEB;--1:#403F">5<3 sp ansty="le--0:#C5E478;--1:#3B61">B0numb1<1)sp ansty="le--0:#7FDBCA;--1:#096E">7<2:sp ansty="le--0:#D6DEEB;--1:#403F">5<3 sp ansty="le--0:#C5E478;--1:#3B61">B0numb53< {d ivclassNa="meec-li">nt< sp ansty="le--0:#C792EA;--1:#8844">AEretu53 valuA5<3 sp ansty="le--0:#F78C6C;--1:#AA09">8<22sp ansty="le--0:#D6DEEB;--1:#403F">5<3;d ivclassNa="meec-li">5<3}d ivclassNa="meec-li">dB0calcula5<3 sp ansty="le--0:#C792EA;--1:#8844">A5<3 sp ansty="le--0:#D9F5DD;--1:#1111">1<1(sp ansty="le--0:#D7DBE0;--1:#403F">53val7<2:sp ansty="le--0:#D6DEEB;--1:#403F">5<3 sp ansty="le--0:#C5E478;--1:#3B61">B0numb1<1)sp ansty="le--0:#D6DEEB;--1:#403F">5<3 sp ansty="le--0:#C792EA;--1:#8844">AE<=>sp ansty="le--0:#D6DEEB;--1:#403F">53 valusp>A5<3 sp ansty="le--0:#F78C6C;--1:#AA09">8<23sp ansty="le--0:#D6DEEB;--1:#403F">5<3;d ivclassNa="meco"><3;d>AEfuncti5<3 sp ansty="le--0:#82AAFF;--1:#3B61">B0processDa11<()sp ansty="le--0:#7FDBCA;--1:#096E">7<2:sp ansty="le--0:#D6DEEB;--1:#403F">5<3 sp ansty="le--0:#C5E478;--1:#3B61">B0vo53< {d ivclassNa="meec-li">53< sp ansty="le--0:#D6DEEB;--1:#403F">53consoAB0l5<3(sp ansty="le--0:#D9F5DD;--1:#1111">1<1"sp ansty="le--0:#ECC48D;--1:#984E">4DProcessing.<..sp ansty="le--0:#D9F5DD;--1:#1111">1<1"sp ansty="le--0:#D6DEEB;--1:#403F">53<);d ivclassNa="meec-li">5<3}d ivclassNa="meec-li">d53processDatA5<3 sp ansty="le--0:#FF6A83;--1:#A248">48nu5<3;d ivclassNa="meco">AEfuncti5<3 sp ansty="le--0:#82AAFF;--1:#3B61">B0getVal11<()sp ansty="le--0:#7FDBCA;--1:#096E">7<2:sp ansty="le--0:#D6DEEB;--1:#403F">5<3 sp ansty="le--0:#C5E478;--1:#3B61">B0numb53< {d ivclassNa="meec-li">nt< sp ansty="le--0:#C792EA;--1:#8844">AEretu5<3 sp ansty="le--0:#F78C6C;--1:#AA09">82<42sp ansty="le--0:#D6DEEB;--1:#403F">5<3;d ivclassNa="meec-li">5<3}d ivclassNa="meec-li">d53getValAE<++sp ansty="le--0:#D6DEEB;--1:#403F">5<3;d ivclassNa="meco"><+;d>
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Options

Section titled “Options”

This rule is not configurable.

When Not To Use It

Section titled “When Not To Use It”

If you’re working in an existing codebase where reassigning function declarations is a common pattern and refactoring would be too costly, you might choose to disable this rule. However, using function expressions or const variables is generally a better practice when reassignment is needed.

Further Reading

Section titled “Further Reading”

Equivalents in Other Linters

Section titled “Equivalents in Other Linters”