Trait StringArgument 

pub trait StringArgument: Sealed + Sized {
    // Required methods
    fn require_non_blank(self, path: &str) -> ArgumentResult<Self>;
    fn require_byte_len(
        self,
        path: &str,
        expected: usize,
    ) -> ArgumentResult<Self>;
    fn require_byte_len_at_least(
        self,
        path: &str,
        min: usize,
    ) -> ArgumentResult<Self>;
    fn require_byte_len_at_most(
        self,
        path: &str,
        max: usize,
    ) -> ArgumentResult<Self>;
    fn require_byte_len_in(
        self,
        path: &str,
        min: usize,
        max: usize,
    ) -> ArgumentResult<Self>;
    fn require_char_count(
        self,
        path: &str,
        expected: usize,
    ) -> ArgumentResult<Self>;
    fn require_char_count_at_least(
        self,
        path: &str,
        min: usize,
    ) -> ArgumentResult<Self>;
    fn require_char_count_at_most(
        self,
        path: &str,
        max: usize,
    ) -> ArgumentResult<Self>;
    fn require_char_count_in(
        self,
        path: &str,
        min: usize,
        max: usize,
    ) -> ArgumentResult<Self>;
}

Validates string arguments while preserving ownership or borrowing.

Byte-length methods count UTF-8 bytes, while character-count methods count Unicode scalar values. Every successful method returns the original value without cloning it. String contents are inspected but never captured in an error. Length failures use LengthMetric::Bytes for byte methods and LengthMetric::UnicodeScalars for character-count methods.

The trait is sealed and implemented only for String and &str.

Required Methods

fn require_non_blank(self, path: &str) -> ArgumentResult<Self>

Requires this string to contain at least one non-whitespace character.

Success returns the original value without cloning. Empty strings and strings whose Unicode scalar values are all whitespace return ArgumentErrorKind::Blank at path.

fn require_byte_len(self, path: &str, expected: usize) -> ArgumentResult<Self>

Requires this string to contain exactly expected UTF-8 bytes.

Success returns the original value without cloning. A different byte length returns ArgumentErrorKind::Length at path.

fn require_byte_len_at_least( self, path: &str, min: usize, ) -> ArgumentResult<Self>

Requires this string to contain at least min UTF-8 bytes.

Success returns the original value without cloning. A smaller byte length returns ArgumentErrorKind::Length at path.

fn require_byte_len_at_most( self, path: &str, max: usize, ) -> ArgumentResult<Self>

Requires this string to contain at most max UTF-8 bytes.

Success returns the original value without cloning. A larger byte length returns ArgumentErrorKind::Length at path.

fn require_byte_len_in( self, path: &str, min: usize, max: usize, ) -> ArgumentResult<Self>

Requires this string’s UTF-8 byte length to lie in min..=max.

The range is validated before the string length. If min > max, this returns ArgumentErrorKind::InvalidLengthConstraint at path; otherwise, an out-of-range length returns ArgumentErrorKind::Length. Success returns the original value without cloning.

fn require_char_count(self, path: &str, expected: usize) -> ArgumentResult<Self>

Requires this string to contain exactly expected Unicode scalar values.

Success returns the original value without cloning. A different scalar count returns ArgumentErrorKind::Length at path.

fn require_char_count_at_least( self, path: &str, min: usize, ) -> ArgumentResult<Self>

Requires this string to contain at least min Unicode scalar values.

Success returns the original value without cloning. A smaller scalar count returns ArgumentErrorKind::Length at path.

fn require_char_count_at_most( self, path: &str, max: usize, ) -> ArgumentResult<Self>

Requires this string to contain at most max Unicode scalar values.

Success returns the original value without cloning. A larger scalar count returns ArgumentErrorKind::Length at path.

fn require_char_count_in( self, path: &str, min: usize, max: usize, ) -> ArgumentResult<Self>

Requires this string’s Unicode scalar count to lie in min..=max.

The range is validated before the character count. If min > max, this returns ArgumentErrorKind::InvalidLengthConstraint at path; otherwise, an out-of-range count returns ArgumentErrorKind::Length. Success returns the original value without cloning.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl StringArgument for &str

fn require_non_blank(self, path: &str) -> ArgumentResult<Self>

Validates Unicode blankness and returns the original borrow.

path identifies a ArgumentErrorKind::Blank failure.

fn require_byte_len(self, path: &str, expected: usize) -> ArgumentResult<Self>

Validates the exact UTF-8 byte length and returns the original borrow.

A mismatch returns ArgumentErrorKind::Length at path.

fn require_byte_len_at_least( self, path: &str, min: usize, ) -> ArgumentResult<Self>

Validates the minimum UTF-8 byte length and returns the original borrow.

A value below min returns ArgumentErrorKind::Length at path.

fn require_byte_len_at_most( self, path: &str, max: usize, ) -> ArgumentResult<Self>

Validates the maximum UTF-8 byte length and returns the original borrow.

A value above max returns ArgumentErrorKind::Length at path.

fn require_byte_len_in( self, path: &str, min: usize, max: usize, ) -> ArgumentResult<Self>

Validates an inclusive UTF-8 byte-length range and returns the borrow.

min > max returns ArgumentErrorKind::InvalidLengthConstraint at path; an out-of-range value returns ArgumentErrorKind::Length.

fn require_char_count(self, path: &str, expected: usize) -> ArgumentResult<Self>

Validates the exact Unicode scalar count and returns the original borrow.

A mismatch returns ArgumentErrorKind::Length at path.

fn require_char_count_at_least( self, path: &str, min: usize, ) -> ArgumentResult<Self>

Validates the minimum Unicode scalar count and returns the original borrow.

A count below min returns ArgumentErrorKind::Length at path.

fn require_char_count_at_most( self, path: &str, max: usize, ) -> ArgumentResult<Self>

Validates the maximum Unicode scalar count and returns the original borrow.

A count above max returns ArgumentErrorKind::Length at path.

fn require_char_count_in( self, path: &str, min: usize, max: usize, ) -> ArgumentResult<Self>

Validates an inclusive Unicode scalar-count range and returns the borrow.

min > max returns ArgumentErrorKind::InvalidLengthConstraint at path; an out-of-range count returns ArgumentErrorKind::Length.

impl StringArgument for String

fn require_non_blank(self, path: &str) -> ArgumentResult<Self>

Validates Unicode blankness and returns the original owned string.

path identifies a ArgumentErrorKind::Blank failure.

fn require_byte_len(self, path: &str, expected: usize) -> ArgumentResult<Self>

Validates the exact UTF-8 byte length and returns the owned string.

A mismatch returns ArgumentErrorKind::Length at path.

fn require_byte_len_at_least( self, path: &str, min: usize, ) -> ArgumentResult<Self>

Validates the minimum UTF-8 byte length and returns the owned string.

A value below min returns ArgumentErrorKind::Length at path.

fn require_byte_len_at_most( self, path: &str, max: usize, ) -> ArgumentResult<Self>

Validates the maximum UTF-8 byte length and returns the owned string.

A value above max returns ArgumentErrorKind::Length at path.

fn require_byte_len_in( self, path: &str, min: usize, max: usize, ) -> ArgumentResult<Self>

Validates an inclusive UTF-8 byte-length range and returns the string.

min > max returns ArgumentErrorKind::InvalidLengthConstraint at path; an out-of-range value returns ArgumentErrorKind::Length.

fn require_char_count(self, path: &str, expected: usize) -> ArgumentResult<Self>

Validates the exact Unicode scalar count and returns the owned string.

A mismatch returns ArgumentErrorKind::Length at path.

fn require_char_count_at_least( self, path: &str, min: usize, ) -> ArgumentResult<Self>

Validates the minimum Unicode scalar count and returns the owned string.

A count below min returns ArgumentErrorKind::Length at path.

fn require_char_count_at_most( self, path: &str, max: usize, ) -> ArgumentResult<Self>

Validates the maximum Unicode scalar count and returns the owned string.

A count above max returns ArgumentErrorKind::Length at path.

fn require_char_count_in( self, path: &str, min: usize, max: usize, ) -> ArgumentResult<Self>

Validates an inclusive Unicode scalar-count range and returns the string.

min > max returns ArgumentErrorKind::InvalidLengthConstraint at path; an out-of-range count returns ArgumentErrorKind::Length.

Implementors