Tags #php #kotlin #bash #go #sql #rust #typescript #html #java #python #files #utils #strings #http #concurrency #async #json #arrays #security #types #crypto #database #dates #format
JavaScript Memoize Function
Caches the result of a pure function keyed by its serialised arguments. On repeated calls with the same inputs the cached value is returned instantly, skipping expensive computation. Supports single and multi-argument functions via JSON key serialisation.
PHP Format Money with Currency
Format an amount of cents as a localized currency string using NumberFormatter from intl. Falls back to a basic sprintf if intl isn't available.
PHP Safe Path Join
Concatenate path segments and produce a normalized canonical path that resists "../" escape attempts. Throws if the result would land outside the given base directory.
Bash Trap Signals for Cleanup
Use `trap` to delete temp files / kill background workers when the script exits — even on Ctrl-C or an unhandled error. Single most-undervalued bash feature.
JavaScript Chunk Array
Splits an array into smaller arrays (chunks) of a specified size. The last chunk may be smaller if the array length is not evenly divisible. Useful for batch processing, pagination, rendering large lists in chunks, and rate-limited API calls.
JavaScript Slugify String
Converts any string into a URL-safe slug: lowercases it, replaces accented characters with ASCII equivalents, strips all non-alphanumeric characters (except hyphens), and collapses multiple hyphens into one. Ideal for generating URL slugs from blog titles, product names, or user input.
Go json.RawMessage — Deferred Decoding
`json.RawMessage` is a `[]byte` that survives a decode pass. Use it for envelope-style JSON where one field's type depends on another (e.g. `{"type":"X","payload":{...}}`).
JavaScript Random Hex Color
Generates a random 6-digit hex colour string. Useful for seeding avatar backgrounds, chart series colours, placeholder UI elements, and testing colour-dependent components. The crypto version produces a more unpredictable result suitable for generating unique palette tokens.
PHP Generate Secure API Key
Mint an API key with a recognizable prefix ("sk_live_…") and 32 bytes of crypto-random entropy encoded as URL-safe base64. Stripe-style readable IDs.
PHP Validate URL (scheme + host)
Beyond filter_var, also require the URL to have an http(s) scheme and a non-empty host. Rejects "javascript:" and other risky pseudo-schemes commonly seen in stored XSS.
SQL EXPLAIN / EXPLAIN ANALYZE
`EXPLAIN` shows the query plan; `EXPLAIN ANALYZE` actually runs it and shows real timings. The first tool when a query is slow — look for sequential scans on big tables.
JavaScript String Template Tag — SQL / HTML Sanitiser
A tagged template literal that automatically escapes interpolated values, preventing SQL injection (server-side) or XSS (client-side) from untrusted input. The html tag HTML-encodes values; the sql tag parameterises values and returns a { text, values } tuple ready for a parameterised query driver.
JavaScript Simple State Machine
A lightweight finite state machine that defines valid states and allowed transitions between them. Attempting an invalid transition throws an error. Supports entry/exit hooks per state for side effects. Useful for modelling UI flows (idle → loading → success/error), auth states, and multi-step forms.
TypeScript Typed Fetch Wrapper
A thin fetch wrapper that returns parsed JSON typed as `T`, throws on non-2xx, and accepts an AbortSignal. Single source of truth for "how this app talks to APIs."
JavaScript Long Polling Helper
Implements a long-polling loop that repeatedly calls a fetch endpoint and invokes a callback with the result. Backs off exponentially on errors and stops cleanly when cancelled via the returned stop function. A simple alternative to WebSockets for low-frequency server-push events without SSE support.
Bash Symlink Force-Update
`ln -s` fails if the target already exists. `ln -sf` is the idempotent variant — useful in deploy scripts that point a "current" symlink to a fresh release directory.
Kotlin Type Aliases
`typealias` gives a shorter / more meaningful name to an existing type. Compile-time only — no new type, no overhead. Great for taming verbose function types or generic parameters.
Kotlin takeIf / takeUnless — Conditional Pipelines
`takeIf { predicate }` returns `this` if the predicate holds, else null. `takeUnless` is the inverse. Combine with `?.let { ... }` for clean conditional transformations.