Results for “du”
Small, practical examples. Search by task or narrow things down below.
Replace an array segment in place
TypeScript: splice returns removed items and inserts replacements at the chosen position.
TypeScript✓ Tested
Replace one collection element
TypeScript: Update an existing element at a known valid index.
TypeScript✓ Tested
Require a checkbox to be selected
HTML: A required checkbox is invalid until that individual control is checked.
HTML✓ Tested
Require two conditions to be true
TypeScript: Combine a lower and an upper bound to check whether a value is in range.
TypeScript✓ Tested
Resolve a relative URL against a base
TypeScript: A trailing slash makes the final base path component a directory.
TypeScript✓ Tested
Return the first item with a generic function
Preserve the element type while allowing empty arrays.
generics✓ Tested
Return typed data from an async function
Await a Promise and handle failures explicitly.
async✓ Tested
Return zero for a sum over no rows
SQL: SUM produces NULL for an empty input; COALESCE supplies the desired reporting default.
SQL✓ Tested
Return zero for a sum over no rows
SQL Server: SUM produces NULL for an empty input; COALESCE supplies the desired reporting default.
SQL Server✓ Tested
Return zero for a sum over no rows
Postgres: SUM produces NULL for an empty input; COALESCE supplies the desired reporting default.
Postgres✓ Tested
Return zero for a sum over no rows
SQLite: SUM produces NULL for an empty input; COALESCE supplies the desired reporting default.
SQLite✓ Tested
Reverse a copy while preserving the original
TypeScript: Copy before reverse because reverse mutates the array it receives.
TypeScript✓ Tested