Struct Generator 

pub struct Generator { /* private fields */ }

A statement writer.

Cheap to build and cheap to clone, and a run is a seed, so the same generator with the same seed writes the same statement on any machine and in any order.

Implementations

impl Generator

pub fn new() -> Self

A generator over the default catalog.

pub fn with_catalog(catalog: Catalog) -> Self

A generator over a catalog somebody else built, which is the case that matters.

pub fn budget(self, tokens: u32) -> Self

How many tokens to write before finishing as cheaply as possible.

pub fn repeats(self, times: u32) -> Self

How many times one rule may appear on the path from the root before the same thing happens.

One is every statement written with no nesting in it at all. Three is a couple of levels of subquery and of arithmetic, which is where the interesting shapes are.

pub fn statement(&self, seed: u64) -> String

One statement, from this seed.

Panics

Never, in the sense that matters: the rule it writes from is one of the 1088 in the table and every_rule_in_the_table_can_be_written_down says every one of those has a finite text.

pub fn from_rule(&self, rule: &str, seed: u64) -> Result<String>

One piece of a statement, from a named rule.

For a harness that wants expressions rather than statements, and for the tests, which are much easier to read over Expression than over Statement.

Errors

There is no rule with that name, or there is and nothing finite can be written from it.

Trait Implementations

impl Clone for Generator

fn clone(&self) -> Generator

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Generator

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Generator

fn default() -> Self

Returns the “default value” for a type.