Results for “Constraints & defaults”
Small, practical examples. Search by task or narrow things down below.
Require a nonempty text value
HTML: The required attribute makes an empty text control fail native constraint validation.
HTML✓ Tested
Require numeric values on a chosen step
HTML: The step interval is measured from the minimum value when one is provided.
HTML✓ Tested
Select a time in quarter-hour increments
HTML: A time step is expressed in seconds, so 900 represents fifteen minutes.
HTML✓ Tested
Validate a structured text identifier
HTML: The pattern attribute matches the entire nonempty input; required handles the empty case.
HTML✓ Tested
Validate the shape of an absolute URL
HTML: A URL input checks syntax, not whether a resource exists or is safe.
HTML✓ Tested
Build a minimum-priority queue
C++: Supply greater as the comparator because priority_queue defaults to the largest value first.
C++✓ Tested
Copy a file without overwriting
C#: File.Copy defaults to refusing a destination that already exists.
C#✓ Tested
Flatten a single nesting level
JavaScript: flat defaults to a depth of one and creates a new array.
JavaScript✓ Tested
Flatten a single nesting level
TypeScript: flat defaults to a depth of one and creates a new array.
TypeScript✓ Tested
Merge configuration maps with override precedence
PowerShell: Copy defaults before applying override keys so the original remains unchanged.
PowerShell✓ Tested
Merge object settings
Use object spread to apply JavaScript overrides to defaults.
JavaScript✓ Tested
Place missing values after known values portably
SQL: A CASE sort key controls NULL placement without relying on engine-specific defaults.
SQL✓ Tested