Standard Grains

Praia ships with a set of standard library grains. These are installed to <libdir>/grains/ and available in any project without installation.

Import them with use:

use "testing"
use "router"
use "colors"

Available grains

Web & Networking

Grain	Description
router	Express-style HTTP routing with path parameters, middleware support
middleware	CORS, JSON body parsing, auth, request IDs for the router
cookie	HTTP cookie parsing and building
session	Server-side session management (in-memory store)

Testing

Grain	Description
testing	Test framework with test(), assertEqual(), done()

Data formats

Grain	Description
csv	CSV parsing and generation
toml	TOML parser
ini	INI file parser
html	HTML utilities
markdown	Markdown processing
template	String templating

Terminal & Output

Grain	Description
colors	ANSI color and style helpers (red, green, bold, RGB, etc.)
progress	Progress bars and spinners
table	Formatted text tables
logger	Structured logging with levels (debug, info, warn, error)

Utilities

Grain	Description
strings	Extended string utilities
collections	Data structure utilities
math	Extended math functions
geometry	Geometry helpers
datetime	Date and time utilities
timers	Timer utilities
uuid	UUID generation
validate	Input validation
args	Command-line argument parsing
diff	Text diffing
sync	Synchronization primitives

Binary & Encoding

Grain	Description
hex	Hex encoding/decoding, integer conversion, hex dumps
re	Advanced regex with named groups, split, escape

Example: testing

use "testing"

testing.test("addition", lam{ in
    testing.assertEqual(1 + 1, 2, nil)
})

testing.done()

Run with praia test to discover and execute test files.

Example: router with middleware

use "router"
use "middleware"
use "logger"

let log = logger.create("API")
let server = router.create()

server.use(middleware.cors())
server.use(middleware.jsonBody())
server.use(logger.middleware(log))

server.get("/", lam{ req, params in
    return http.json({message: "hello"})
})

server.listen(8080)

Example: colors

use "colors"

print(colors.red("error:") + " something went wrong")
print(colors.green("ok"))
print(colors.bold(colors.blue("important")))
print(colors.rgb("custom color", 255, 128, 0))

Example: progress bar

use "progress"

let p = progress.bar({width: 30, showCount: true})
p.total(100)

for (i in 0..101) {
    p.update(i)
    time.sleep(10)
}
p.done()

Example: table

use "table"

let users = [
    {name: "Alice", age: 30, role: "admin"},
    {name: "Bob", age: 25, role: "user"}
]
print(table.render(users))

Example: hex

use "hex"

hex.encode("Hello")          // "48656c6c6f"
hex.decode("48656c6c6f")     // "Hello"
hex.fromInt(255, 4)          // "00ff"
hex.toInt("0xDEADBEEF")     // 3735928559
print(hex.dump("Hello, World!\n"))