Lookups — `miri view`

Agents often guess method names from other languages: .len(), .to_string(), .keys(). miri view answers from the real standard library instead, so one lookup replaces a string of wrong guesses.

What can I call on a type? Members a type gets from its traits are listed too:

$ miri view --type String --public
class String implements Equatable, Hashable, Comparable, Addable, Multiplicable, Iterable, Cloneable
    fn clone() String
    fn code_at(index int) int?
    fn compare(other String) int
    fn concat(other String) String
    fn contains(needle String) bool
    fn element_at(index int) String
    fn ends_with(suffix String) bool
    fn equals(other String) bool
    static fn from_code_point(code int) String?
    fn hash() int
    fn init() String
    fn is_empty() bool
    fn join(parts [String]) String
    fn length() int
    fn repeat(count int) String
    fn replace(old String, to String) String
    fn size() int
    fn split(separator String) [String]
    fn starts_with(prefix String) bool
    fn substring(start int, end int) String
    fn to_float() float?
    fn to_int() int?
    fn to_lower() String
    fn to_upper() String
    fn trim() String
    fn trim_end() String
    fn trim_start() String
exit status 0

What does a module offer?

$ miri view system.fs --outline --public
use system.result
use system.string
// Represents a filesystem operation error.
@non_exhaustive
public enum FsError
    NotFound(String)
    PermissionDenied(String)
    AlreadyExists(String)
    NotADirectory(String)
    InvalidData(String)
    Other(String)
// Filesystem capability class. Acquire a handle with `let fs = Fs()` to access filesystem operations.
public class Fs
    // Checks whether a file or directory exists at the given path.
    public fn exists(path String) bool
    // Reads the entire contents of a file into a string.
    public fn read_file(path String) Result<String, FsError>
    // Writes the given contents to a file, truncating if it exists.
    public fn write_file(path String, contents String) Result<int, FsError>
    // Appends the given contents to a file, creating it if it doesn't exist.
    public fn append_file(path String, contents String) Result<int, FsError>
    // Lists the entries (file and directory names) in a directory.
    public fn list_dir(path String) Result<[String], FsError>
    // Creates a directory at the given path, creating missing parents as needed.
    public fn create_dir(path String) Result<bool, FsError>
    // Deletes a regular file at the given path.
    public fn delete(path String) Result<bool, FsError>
    // Returns the current working directory as an absolute path.
    public fn cwd() Result<String, FsError>
exit status 0

Show me one function, from a module or from a file of your own:

$ miri view scores.mi --fn total_of_passing
fn total_of_passing(scores [int]) int
    var total = 0
    for s in scores
        if s >= 5: total = total + s
    total
exit status 0

miri view --stdlib-root prints where the standard library is searched for. Set MIRI_STDLIB_PATH if the compiler cannot find it.

Lookups — miri view

Lookups — `miri view`