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What does console.log('Hello'.at(-1)) print? JavaScript Numbers, Strings and Regular Expressions
Block 7, Numbers, Strings and Regular Expressions, question 20 of the JavaScript sample
console.log('Hello'.at(-1))What does this print?
Show the answer and why each option is right or wrong
Answer, A. o
- A. o
- Correct. The at method supports negative indices, and -1 refers to the last character of the string.
- B. H
- Assumes a negative index to at counts from the start of the string instead of from the end.
- C. undefined
- Assumes a negative index is out of range and produces undefined, but at is specifically designed to support negative indices counting from the end.
- D. olleH
- Confuses at with reversing the whole string instead of indexing a single character from the end.
The at method was added to let negative indices count backward from the end of a string or array, unlike bracket indexing, which only accepts non negative positions. Index -1 with at always refers to the very last character.
The answer above is what the Node interpreter printed when the snippet was run, not what someone expected it to do.
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