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defaultCaseLast

Reports switch statements where the default clause is not last.

✅ This rule is included in the ts logical and logicalStrict presets.

When a default clause appears before other case clauses in a switch statement, it can lead to confusion about the control flow. While the default clause will still only execute when no other case matches, placing it in the middle or at the beginning makes the code harder to understand. Convention and readability are improved by keeping the default clause at the end of switch statements.

Examples

Section titled “Examples”
AEfuncti5<3 sp ansty="le--0:#82AAFF;--1:#3B61">B0getDescripti1<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">B0stri53< {d ivclassNa="meec-li">nt< sp ansty="le--0:#C792EA;--1:#8844">AEswit53 (value)< {d ivclassNa="meec-li">nt < sp ansty="le--0:#C792EA;--1:#8844">AEdefau5<3:d ivclassNa="meec-li">nt < sp ansty="le--0:#C792EA;--1:#8844">AEretu5<3 sp ansty="le--0:#D9F5DD;--1:#1111">1<1"sp ansty="le--0:#ECC48D;--1:#984E">4Dunkno1<1"sp ansty="le--0:#D6DEEB;--1:#403F">5<3;d ivclassNa="meec-li">nt < sp ansty="le--0:#C792EA;--1:#8844">AEca5<3 sp ansty="le--0:#F78C6C;--1:#AA09">8<21sp ansty="le--0:#D6DEEB;--1:#403F">5<3:d ivclassNa="meec-li">nt < sp ansty="le--0:#C792EA;--1:#8844">AEretu5<3 sp ansty="le--0:#D9F5DD;--1:#1111">1<1"sp ansty="le--0:#ECC48D;--1:#984E">4Do1<1"sp ansty="le--0:#D6DEEB;--1:#403F">5<3;d ivclassNa="meec-li">nt < sp ansty="le--0:#C792EA;--1:#8844">AEca5<3 sp ansty="le--0:#F78C6C;--1:#AA09">8<22sp ansty="le--0:#D6DEEB;--1:#403F">5<3:d ivclassNa="meec-li">nt < sp ansty="le--0:#C792EA;--1:#8844">AEretu5<3 sp ansty="le--0:#D9F5DD;--1:#1111">1<1"sp ansty="le--0:#ECC48D;--1:#984E">4Dt1<1"sp ansty="le--0:#D6DEEB;--1:#403F">5<3;d ivclassNa="meec-li">53< sp ansty="le--0:#D6DEEB;--1:#403F">5<3}d ivclassNa="meec-li">5<3}d ivclassNa="meec-li">dAEfuncti5<3 sp ansty="le--0:#82AAFF;--1:#3B61">B0processVal1<1(sp ansty="le--0:#D7DBE0;--1:#403F">53inp7<2:sp ansty="le--0:#D6DEEB;--1:#403F">5<3 sp ansty="le--0:#C5E478;--1:#3B61">B0stri1<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">B0vo53< {d ivclassNa="meec-li">nt< sp ansty="le--0:#C792EA;--1:#8844">AEswit53 (input)< {d ivclassNa="meec-li">nt < sp ansty="le--0:#C792EA;--1:#8844">AEca5<3 sp ansty="le--0:#D9F5DD;--1:#1111">1<1"sp ansty="le--0:#ECC48D;--1:#984E">4Dsta1<1"sp ansty="le--0:#D6DEEB;--1:#403F">5<3: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">4DStarting.<..sp ansty="le--0:#D9F5DD;--1:#1111">1<1"sp ansty="le--0:#D6DEEB;--1:#403F">53<);d ivclassNa="meec-li">nt < sp ansty="le--0:#C792EA;--1:#8844">AEbre5<3;d ivclassNa="meec-li">nt < sp ansty="le--0:#C792EA;--1:#8844">AEdefau5<3: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">nt < sp ansty="le--0:#C792EA;--1:#8844">AEbre5<3;d ivclassNa="meec-li">nt < sp ansty="le--0:#C792EA;--1:#8844">AEca5<3 sp ansty="le--0:#D9F5DD;--1:#1111">1<1"sp ansty="le--0:#ECC48D;--1:#984E">4De1<1"sp ansty="le--0:#D6DEEB;--1:#403F">5<3: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">4DEnding.<..sp ansty="le--0:#D9F5DD;--1:#1111">1<1"sp ansty="le--0:#D6DEEB;--1:#403F">53<);d ivclassNa="meec-li">nt < sp ansty="le--0:#C792EA;--1:#8844">AEbre5<3;d ivclassNa="meec-li">53< sp ansty="le--0:#D6DEEB;--1:#403F">5<3}d ivclassNa="meec-li">5<3}d ivclassNa="meco"><}d>
44AEfunc361B0getDescrip1<111( spans="tyle--0:#D7DBE0;--1:#40">3F53v6361B0nu1<111) spans="tyle--0:#7FDBCA;--1:#09">6361B0st3F<53 {divclass="Nameec-">de44AEsw3F53 (valudent< spans="tyle--0:#C792EA;--1:#88">44AE30<9821 spans="tyle--0:#D6DEEB;--1:#40">3dent < spans="tyle--0:#C792EA;--1:#88">44AEre31<111" spans="tyle--0:#ECC48D;--1:#98">4E41<111" spans="tyle--0:#D6DEEB;--1:#40">3dent< spans="tyle--0:#C792EA;--1:#88">44AE30<9822 spans="tyle--0:#D6DEEB;--1:#40">3dent < spans="tyle--0:#C792EA;--1:#88">44AEre31<111" spans="tyle--0:#ECC48D;--1:#98">4E41<111" spans="tyle--0:#D6DEEB;--1:#40">3dent< spans="tyle--0:#C792EA;--1:#88">44AEdef3dent < spans="tyle--0:#C792EA;--1:#88">44AEre31<111" spans="tyle--0:#ECC48D;--1:#98">4E4Dunk1<111" spans="tyle--0:#D6DEEB;--1:#40">33F<53 spans="tyle--0:#D6DEEB;--1:#40">33c44AEfunc361B0processV1<111( spans="tyle--0:#D7DBE0;--1:#40">3F53i6361B0st1<111) spans="tyle--0:#7FDBCA;--1:#09">6361B03F<53 {divclass="Nameec-">de44AEsw3F53 (inpudent< spans="tyle--0:#C792EA;--1:#88">44AE31<111" spans="tyle--0:#ECC48D;--1:#98">4E4Ds1<111" spans="tyle--0:#D6DEEB;--1:#40">33F53 < spans="tyle--0:#D6DEEB;--1:#40">3F53con4<4AE. spans="tyle--0:#82AAFF;--1:#3B">61B<0log spans="tyle--0:#D6DEEB;--1:#40">31<111" spans="tyle--0:#ECC48D;--1:#98">4E4DStartin1<111" spans="tyle--0:#D6DEEB;--1:#40">3F<53) ;divclass="Nameec-">dent < spans="tyle--0:#C792EA;--1:#88">44AEb3dent< spans="tyle--0:#C792EA;--1:#88">44AE31<111" spans="tyle--0:#ECC48D;--1:#98">4E41<111" spans="tyle--0:#D6DEEB;--1:#40">33F53 < spans="tyle--0:#D6DEEB;--1:#40">3F53con4<4AE. spans="tyle--0:#82AAFF;--1:#3B">61B<0log spans="tyle--0:#D6DEEB;--1:#40">31<111" spans="tyle--0:#ECC48D;--1:#98">4E4DEndin1<111" spans="tyle--0:#D6DEEB;--1:#40">3F<53) ;divclass="Nameec-">dent < spans="tyle--0:#C792EA;--1:#88">44AEb3dent< spans="tyle--0:#C792EA;--1:#88">44AEdef33F53 < spans="tyle--0:#D6DEEB;--1:#40">3F53con4<4AE. spans="tyle--0:#82AAFF;--1:#3B">61B<0log spans="tyle--0:#D6DEEB;--1:#40">31<111" spans="tyle--0:#ECC48D;--1:#98">4E4DProcessin1<111" spans="tyle--0:#D6DEEB;--1:#40">3F<53) ;divclass="Nameec-">dent < spans="tyle--0:#C792EA;--1:#88">44AEb33F<53 spans="tyle--0:#D6DEEB;--1:#40">33< }>

Options

Section titled “Options”

This rule is not configurable.

When Not To Use It

Section titled “When Not To Use It”

If you have a specific code style guide that requires default clauses to appear in a different position, you might choose to disable this rule. However, this is generally not recommended as it goes against common JavaScript conventions.

Further Reading

Section titled “Further Reading”

Equivalents in Other Linters

Section titled “Equivalents in Other Linters”