JavaScript: Default parameters
Consider the round() function, which rounds an integer:
const result = round(10.25, 0); // 10
We pass two parameters to it: the number to round and the precision of rounding. 0 means that it will round to an integer, and the decimal part will simply be discarded.
In most cases, we need to round exactly to an integer (and not to tenths, for example), so designers of the round() function have made the second parameter optional and set it to a default value of 0. So, you can choose to not specify the second parameter and the result will be the same:
const result = round(10.25); // 10
We can specify precision by passing another parameter:
// rounding to one decimal place
const result = round(10.25, 1); // 10.3
If a JavaScript function accepts optional arguments, they always come after the required ones. Their number varies depending on the function itself, but they always go next to each other and at the end of the list of arguments.
Instructions
Round up the value of the constant number to two decimal places and print the result.
Definitions
- Default parameter
- is an optional function parameter.
The exercise doesn't pass checking. What to do? 😶
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In my environment the code works, but not here 🤨
Tests are designed so that they test the solution in different ways and against different data. Often the solution works with one kind of input data but doesn't work with others. Check the «Tests» tab to figure this out, you can find hints at the error output.
My code is different from the teacher's one 🤔
It's fine. 🙆 One task in programming can be solved in many different ways. If your code passed all tests, it complies with the task conditions.
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I've read the lessons but nothing is clear 🙄
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Your exercise will be checked with these tests:
1import { expectOutput } from 'hexlet-basics/tests';
2
3const expected = '10.12';
4expectOutput(expected);
5Teacher's solution will be available in:
