std.env | Zero

When To Use std.env

In Zerolang, use std.env for hosted environment variable lookup and simple typed configuration values.

Runnable today:

API	Return	Notes
`std.env.get(name)`	`Maybe<String>`	Returns a hosted process environment value when present.
`std.env.has(name)`	`Bool`	Reports whether a hosted environment variable exists.
`std.env.getOr(name, fallback)`	`String`	Returns the environment value or a caller-provided fallback.
`std.env.equals(name, expected)`	`Bool`	Compares an environment value with expected text without exposing a missing value as success.
`std.env.parseBool(name)`	`Maybe<Bool>`	Parses an environment value as `Bool`.
`std.env.parseBoolOr(name, fallback)`	`Bool`	Parses a boolean environment value or returns a caller-provided fallback.
`std.env.parseI32(name)`	`Maybe<i32>`	Parses an environment value as `i32`.
`std.env.parseI32Or(name, fallback)`	`i32`	Parses an `i32` environment value or returns a caller-provided fallback.
`std.env.parseU32(name)`	`Maybe<u32>`	Parses an environment value as `u32`.
`std.env.parseU32Or(name, fallback)`	`u32`	Parses a `u32` environment value or returns a caller-provided fallback.
`std.env.parseUsize(name)`	`Maybe<usize>`	Parses an environment value as `usize`.
`std.env.parseUsizeOr(name, fallback)`	`usize`	Parses a `usize` environment value or returns a caller-provided fallback.

Current limits:

Dotenv/source composition.
Secret redaction metadata.
Rich diagnostics for missing keys, invalid values, and source precedence.

Example

pub fn main(world: World) -> Void raises {    let mode: String = std.env.getOr("ZERO_MODE", "default")    let verbose: Bool = std.env.parseBoolOr("ZERO_VERBOSE", false)    let delta: i32 = std.env.parseI32Or("ZERO_DELTA", 0)    let limit: u32 = std.env.parseU32Or("ZERO_LIMIT", 10)    let workers: usize = std.env.parseUsizeOr("ZERO_WORKERS", 1)    if std.env.equals("ZERO_MODE", "debug") && verbose && delta >= 0 && limit > 0_u32 && workers > 0 {        check world.out.write(mode)        check world.out.write("\n")    } else {        check world.out.write("default\n")    }}

Design Notes

Environment access is a hosted capability. Non-host targets reject std.env unless they explicitly provide an environment capability.

Diagnostics name the selected target context.