Struct Ident 

pub struct Ident(/* private fields */);

An identifier.

Implementations

impl Ident

pub const MAX_LENGTH: usize = MAX_IDENTIFIER_LENGTH

Maximum length of an identifier in Materialize.

pub fn new<S>(s: S) -> Result<Self, IdentError>

where S: TryInto<IdentString>, <S as TryInto<IdentString>>::Error: Display,

Create a new Ident with the given value, checking our invariants.

Examples

use mz_sql_parser::ast::Ident;

let id = Ident::new("hello_world").unwrap();
assert_eq!(id.as_str(), "hello_world");

let too_long = "I am a very long identifier that is more than 255 bytes long which is the max length for idents.\
😊😁😅😂😬🍻😮‍💨😮🗽🛰️🌈😊😁😅😂😬🍻😮‍💨😮🗽🛰️🌈😊😁😅😂😬🍻😮‍💨😮🗽🛰️🌈";
assert_eq!(too_long.len(), 258);

let too_long_id = Ident::new(too_long);
assert!(too_long_id.is_err());

let invalid_name_dot = Ident::new(".");
assert!(invalid_name_dot.is_err());

let invalid_name_dot_dot = Ident::new("..");
assert!(invalid_name_dot_dot.is_err());

pub fn new_lossy<S: Into<String>>(value: S) -> Self

Create a new Ident modifying the given value as necessary to meet our invariants.

Examples

use mz_sql_parser::ast::Ident;

let too_long = "🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢\
🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵\
🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴";

let id = Ident::new_lossy(too_long);

// `new_lossy` will truncate the provided string, since it's too long. Note the missing
// `🔴` characters.
assert_eq!(id.as_str(), "🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵");

pub fn new_unchecked<S: Into<String>>(value: S) -> Self

Create a new Ident without checking any of our invariants.

NOTE: Generally you should not use this function! If you’re trying to create an Ident from a &'static str you know is valid, use the ident! macro. For all other use cases, see Ident::new which correctly checks our invariants.

pub fn try_generate_name<P, S, F, E>( prefix: P, suffix: S, is_valid: F, ) -> Result<Self, E>

where P: Into<String>, S: Into<String>, E: From<IdentError>, F: FnMut(&Ident) -> Result<bool, E>,

Generate a valid Ident with the provided prefix and suffix.

Examples

use mz_sql_parser::ast::{Ident, IdentError};

let good_id =
  Ident::try_generate_name("hello", "_world", |_| Ok::<_, IdentError>(true)).unwrap();
assert_eq!(good_id.as_str(), "hello_world");

// Return invalid once.
let mut attempts = 0;
let one_failure = Ident::try_generate_name("hello", "_world", |_candidate| {
    if attempts == 0 {
        attempts += 1;
        Ok::<_, IdentError>(false)
    } else {
        Ok(true)
    }
})
.unwrap();

// We "hello_world" was invalid, so we appended "_1".
assert_eq!(one_failure.as_str(), "hello_world_1");

pub fn append_lossy<S: Into<String>>(&mut self, suffix: S)

Append the provided suffix, truncating self as necessary to satisfy our invariants.

Note: We soft-assert that the provided suffix is not too long, if it is, we’ll truncate it.

Examples

use mz_sql_parser::{
    ident,
    ast::Ident,
};

let mut id = ident!("🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵🔵");
id.append_lossy("🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴");

// We truncated the original ident, removing all '🔵' chars.
assert_eq!(id.as_str(), "🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴🔴");

Too long suffix

If the provided suffix is too long, we’ll also truncate that.

use mz_sql_parser::{
    ident,
    ast::Ident,
};

let mut stem = ident!("hello___world");

let too_long_suffix = "\
🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢\
🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢\
🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢\
🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🔵🔵\
";

stem.append_lossy(too_long_suffix);

// Notice the "hello___world" stem got truncated, as did the "🔵🔵" characters from the suffix.
let result = "hello___wor\
🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢\
🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢\
🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢\
🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢🟢\
";
assert_eq!(stem.as_str(), result);

pub fn has_only_bare_chars(&self) -> bool

Reports whether the identifier matches the regex [a-z_][a-z0-9_]*, i.e. it is composed only of characters that never require quoting.

This is the character-level half of Ident::can_be_printed_bare. It deliberately does not consider keywords: whether a keyword-named identifier needs quoting depends on the surrounding grammar (a reparsing concern), not on its characters. Contexts that only need legible, unambiguous output — rather than a SQL round-trip — should use this instead (see HumanizedExplain::humanize_ident).

pub fn can_be_printed_bare(&self) -> bool

An identifier can be printed in bare mode if

• it matches the regex [a-z_][a-z0-9_]* and
• it is not a “reserved keyword.”

pub fn as_str(&self) -> &str

pub fn as_keyword(&self) -> Option<Keyword>

pub fn into_string(self) -> String

Trait Implementations

impl AstDisplay for Ident

More-or-less a direct translation of the Postgres function for doing the same thing:

https://github.com/postgres/postgres/blob/master/src/backend/utils/adt/ruleutils.c#L10730-L10812

Quotation is forced when printing in Stable mode.

fn fmt<W: Write>(&self, f: &mut AstFormatter<W>)

fn to_ast_string_simple(&self) -> String

fn to_ast_string_stable(&self) -> String

fn to_ast_string_redacted(&self) -> String

fn to_ast_string(&self, format_mode: FormatMode) -> String

impl Clone for Ident

fn clone(&self) -> Ident

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Ident

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Ident

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for Ident

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

Formats the value using the given formatter.

impl<T: AstInfo, T2: AstInfo> FoldNode<T, T2> for Ident

type Folded = Ident

fn fold<F: Fold<T, T2>>(self, folder: &mut F) -> Self::Folded

impl From<Ident> for Value

fn from(ident: Ident) -> Self

Converts to this type from the input type.

impl From<Keyword> for Ident

fn from(value: Keyword) -> Ident

Converts to this type from the input type.

impl Hash for Ident

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Ident

fn cmp(&self, other: &Ident) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Ident

fn eq(&self, other: &Ident) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Ident

fn partial_cmp(&self, other: &Ident) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for Ident

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl<'ast, T: AstInfo> VisitMutNode<'ast, T> for Ident

fn visit_mut<V: VisitMut<'ast, T>>(&'ast mut self, visitor: &mut V)

impl<'ast, T: AstInfo> VisitNode<'ast, T> for Ident

fn visit<V: Visit<'ast, T>>(&'ast self, visitor: &mut V)

impl Eq for Ident

impl StructuralPartialEq for Ident