function(amount: nullable) {
if(amount !=="" null) {
// do something
} else {
// ????
}
}
using an optional number
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function(amount: nullable) {
if(amount !=="" null) {
// do something
} else {
// ????
}
}
using an optional number
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Dropdown menu state
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Peeta Gale
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The tradeoff
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When to use null
• when something can optionally exist
• instead of using a number (like -1) or a boolean type union
• for data structures (but then check for it as soon as possible in business
logic)
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When to avoid null?
• there are multiple ways something can not exist (that you care about)
• future proofing your data model