aburtang@lemmy.world to Programmer Humor · 1 month agoEvil Oneslemmy.worldimagemessage-square79fedilinkarrow-up11.01Karrow-down130
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minus-squarepooberbee (they/she)linkfedilinkarrow-up2arrow-down1·1 month agoYeah, you would get a runtime error calling that member without checking that it exists.
minus-squaremasterspace@lemmy.calinkfedilinkEnglisharrow-up1·edit-227 days agoBecause that object is of a type where that member may or may not exist. That is literally the exact same behaviour as Java or C#. If I cast or type check it to make sure it’s of type Bar rather than checking for the member explicitly it still works: And when I cast it to Foo it throws a compile time error, not a runtime error: I think your issues may just like in the semantics of how Type checking works in JavaScript / Typescript.
Yeah, you would get a runtime error calling that member without checking that it exists.
Because that object is of a type where that member may or may not exist. That is literally the exact same behaviour as Java or C#.
If I cast or type check it to make sure it’s of type Bar rather than checking for the member explicitly it still works:
And when I cast it to Foo it throws a compile time error, not a runtime error:
I think your issues may just like in the semantics of how Type checking works in JavaScript / Typescript.