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Share and discover code snippetsCoalesce Null Default
Returns the first non-null value from a list of expressions, using a default if all are null.
vshepard
Ternary null coalescing
Assigns a default value when a variable is null, using PHP's shorter null coalescing operator.
reginald
Strict Type Predicate
A TypeScript utility that creates a type guard function to verify if a value matches a specific type at runtime, ensuring type safety when working with uncertain data.
angelaa
concurrent HTTP requests
A Go code snippet that fires off multiple HTTP requests in parallel using goroutines and a sync.WaitGroup to handle them concurrently.
joshua
Sort array descending
This Rust code snippet sorts an array in descending order using the sortby method with a comparison closure.
julia
Array destructuring swap
Swaps two variables without a temporary variable using array destructuring.
sarahhall
Center with Flexbox
This CSS snippet centers any child element both horizontally and vertically inside a flex container.
julia
Array Shuffle Fisher Yates
Shuffles an array in place using the Fisher-Yates algorithm for uniform random distribution.
erin1992
Array destructuring swap
Swaps two values without a temporary variable by using array destructuring assignment.
mvargas
Hash String Comparison
Compares two strings by their hash values to check for equality efficiently.
Hashing for equality works great until you hit a collision, and then you're stuck debugging a false positive that looks like a bug in your comparison logic.
mvargas
Iterate with enumerate
Enumerate in Rust lets you iterate over a collection while automatically tracking the index of each element.
charlesl
Async file read
This snippet reads the contents of a file asynchronously using Tokio's tokio::fs::readtostring function.
mvargas
Ternary inline condition
Returns one of two values based on a true or false condition, mimicking an if-else statement in a single line.
ryan_adams
COALESCE for defaults
Returns the first non-null value from a list, making it easy to set fallback defaults for missing data.
stephaniem
Flexbox Center Alignment
This snippet centers a child element both horizontally and vertically within its parent using Flexbox.
coxa
Stream collect toList
Converts a stream of elements into a mutable List in Java.
deanna_avila
truncate cascade tables
This SQL snippet drops all dependent foreign key relationships before truncating a table.
samuel
File exists check
This Bash snippet returns true before attempting to write if a file exists, preventing overwrite errors.
tommy_washington
short usefull code
This Java snippet checks if a string is null or empty in a single line.
mklein
PHP array map filter
Applies a callback to each element of an array, then filters the results based on a condition.
estradap
Split string by delimiter
Splits a string into a table of substrings using a specified delimiter.
stephaniem
re.sub cleanup string
This Python snippet uses regex to remove unwanted characters or patterns from a string.
michaelsimmons
Move Semantics Example
This snippet demonstrates efficient resource transfer by using move semantics to avoid expensive deep copies when passing temporary objects.
joanhouse
The null coalescing operator (
??) works well for undefined keys too, not just null values. In your example,$username ?? 'guest'avoids an undefined index notice if$usernameisn't set, which the ternary operator (isset($username) ? $username : 'guest') also handles but with more syntax. Just watch for nested coalescing, as it evaluates left to right and can mask deeper null issues in chained calls like$a ?? $b ?? $c.