Reference · General

env

env(str, any=) -> any

What it does

The value of an environment variable, as a string, or null when it is not set; with a second argument, that default instead of null. The .env beside the program is read into the environment when the program starts, and a variable the environment already has wins over the file. A component cannot call env, except for a variable named PUBLIC_..., whose value is written into the browser's bundle as it was when the program loaded.

Examples

print(env("HOME") != null, type_of(env("HOME")))print(env("MISSING_QUILLO_VAR"), env("MISSING_QUILLO_VAR", "fallback"))

true strnull fallback

Edge cases

• The value is always a string: a port or a count is converted with int, and ?? gives the default when the variable is missing.
• The default can be any value, not only a string: env("X", 42) is 42 when X is not set.
• A variable that is set to the empty string is "", not null, so its default is not used. In the .env, # ends a bare value, so KEY= # set me is "" while KEY=#fff is #fff.
• Only a .env that is not there is nothing. One that cannot be read, is not UTF-8, or is a link to nothing stops the start with exit 2, saying where and the ways out (quillo: cannot read .env: it is not UTF-8 text: byte 0xE9 at line 1, column 9 (save it as UTF-8); to start without it, remove it or give `--env-file /dev/null` ). A line that is not KEY=value, or whose value holds a NUL byte, is skipped and said at the start; a quote never closed skips its own line only.
• Under a policy whose [env] gives names (/etc/quillo/policy.toml, quillo run main.qwe --policy FILE or quillo.policy beside the program; see the options), a name not in the list reads as not set: null, or the default. Each policy file can only narrow the list.

let port = int(env("PORT") ?? "3000")print(port, type_of(port))print(env("MISSING_QUILLO_VAR", 42))print(len(env("PATH") ?? "") > 0)

3000 int42true

let KEY = env("STRIPE_KEY")               // on the server: fine at the top levelcomponent Map() {    let token = env("PUBLIC_MAP_TOKEN")   // in a component: only a PUBLIC_ name    <div data-token={token}></div>}

Errors

A name that is not a string is a runtime error, not an error value. A missing variable is never an error: it is null or the default. Using env in a component, or a top-level value made from it, is refused when the program loads.

print(env(42))

line 1: `env` expects a str as argument 1, got int

Chaining

print(env("HOME") | contains("/"))print(env("MISSING_QUILLO_VAR") ?? "none" | upper)let [host, port] = split(env("LISTEN") ?? "0.0.0.0:3000", ":")print(host, int(port))

trueNONE0.0.0.0 3000

See also

int, str, db.open, read_file

Edit this page on GitHub · every example's output was made by running it (tools/refcheck.mjs) · questions on Discord or r/quillo