silk.core.static_text.

When to use#

Use StaticText to check or build text at compile time, such as to parse a format template and report an error in the compiler. Use silk.text.string.String for text at runtime.

Details#

The operations work on UTF-8 bytes. They run only during static evaluation. The results are static values, so they add no runtime cost.

Examples#

Measure a literal at compile time#

import silk.core.static_text { StaticText }

static fn greeting() -> string<'static> {
  return StaticText.concat("hello, ", "world")
}

static fn greetingLength() -> usize {
  return StaticText.byteLength(greeting())
}

pub fn main() -> i32 {
  let length = greetingLength()
  if length != 12 {
    return 1
  }
  return 0
}

Import as StaticText with import silk.core.static_text { StaticText }.

Public declarations: 1.

StaticText#

pub struct StaticText

The owner type of the static text operations. It has no fields and is never constructed.

Details#

Each operation is static. It runs only during static evaluation, such as in a static fn, a static for, or a const initializer.

Implementation StaticText#

impl StaticText

Associated function byteLength#

pub static fn byteLength(value: string) -> usize

Returns the number of UTF-8 bytes in value. This is not the number of characters.

Associated function byteAt#

pub static fn byteAt(value: string, index: usize) -> u8

Returns the UTF-8 byte at the zero-based byte position index of value.

Gotchas#

If index is not less than StaticText.byteLength, static evaluation stops and the compiler reports an error.

Associated function concat#

pub static fn concat(left: string, right: string) -> string<'static>

Returns left followed by right.

Details#

A compiler error about the result points to the source location of left.

Associated function slice#

pub static fn slice(value: string, start: usize, end: usize) -> string<'static>

Returns the bytes of value from byte position start to byte position end, with end not included.

Gotchas#

start and end must be at character boundaries, with start <= end <= byteLength(value). Otherwise, static evaluation stops and the compiler reports an error.

Category: Core.

Profiles: aarch64-apple-darwin, aarch64-unknown-linux-gnu, aarch64-unknown-linux-gnu-no-libc, x86_64-unknown-linux-gnu, x86_64-unknown-linux-gnu-no-libc, wasm32-unknown-unknown, wasm32-wasip1, wasm32-wasip2.