For a code snippet with a function call before its assignment to a variable, for example var foo = function () {}, determine the execution result and explain hoisting.
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143
Frontend
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681
How would you organize style isolation for each micro-frontend, including when using Tailwind CSS? What browser approaches for isolation exist?
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143
Implement your own utility type Pick<T, K>. Explain how mapped types work and how to implement an equivalent of Partial<T>.
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142
How does display: none differ from opacity: 0 in terms of render tree, layout, and occupied space? Which option is more performant and why?
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137
How have you worked with React: which versions have you encountered and have you used class components? How do class components differ from functional ones?
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137
If an object is created using Object.create([object]), what will its __proto__ point to?
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135
What does the render tree include? Which elements are considered hidden?
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132
For the Promise.resolve(1).then(() => { throw 2 }).then(...).catch(x => console.log(x)).then(x => console.log(x)), determine what will be in the last console.log, and explain why.
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131
Does the value [object] have a prototype? How does __proto__ differ from prototype? What does __proto__ of an object point to? Is it true that __proto__ exists on all values?
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130
What does useMemo do and what are the consequences of using it for all values unnecessarily?
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128
Please tell us about yourself and your last project: what you worked on and what difficult or interesting cases you encountered?
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128
For a code snippet with reduce and an initial accumulator of 10, determine what console.log will output.
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125
If the loadRolesData function returns a Promise, what will be the value after its call? Is it possible to store a Promise in a state intended for data, and how to fix this?
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125
For a recursive call of a function inside a Promise handler, determine the order of execution and explain whether it will result in an infinite loop.
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125
What is the name of the check like if ('payload' in data), used for narrowing the type?
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123
For a for loop with var and setTimeout, determine what will be output. How to modify the code so that with var, the values 1, 2, 3 are output, rather than the final counter value?
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122
For a code fragment with the array [1, 2, 3], calls to map(item => item * 2) and filter(item => item > 3), determine what console.log will output. Do map and filter mutate the original array?
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120
What is the name of and how is the approach implemented, where the same input data results in sending one request instead of multiple identical ones?
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119
What is the difference between interface and type in TypeScript?
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118
What is the difference between a regular script, a script with async, and a script with defer? If there are multiple script tags on a page, in what order will they load and execute?
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114