Module format

lexical_core

Module format 

Source
Expand description

The creation and processing of number format packed structs.

This creates the format specification as a 128-bit packed struct, represented as a u128 through the NumberFormatBuilder and with helpers to access format options through NumberFormat.

This has a consistent API whether or not the format feature is enabled, however, most functionality will be disabled if the feature is not enabled.

§Creating Formats

Formats can be created through NumberFormatBuilder:

use core::num;

use lexical_util::{NumberFormat, NumberFormatBuilder};

// create the format for literal Rustt floats
const RUST: u128 = NumberFormatBuilder::new()
   .digit_separator(num::NonZeroU8::new(b'_'))
   .required_digits(true)
   .no_positive_mantissa_sign(true)
   .no_special(true)
   .internal_digit_separator(true)
   .trailing_digit_separator(true)
   .consecutive_digit_separator(true)
   .build_strict();

// then, access the formats's properties
let format = NumberFormat::<{ RUST }> {};
assert!(format.no_positive_mantissa_sign());
assert!(format.no_special());
assert!(format.internal_digit_separator());
assert!(format.trailing_digit_separator());
assert!(format.consecutive_digit_separator());
assert!(!format.no_exponent_notation());

These pre-built formats can then be used for FromLexicalWithOptions and ToLexicalWithOptions conversions.

§Pre-Defined Formats

These are the pre-defined formats for parsing numbers from various programming, markup, and data languages.

  • STANDARD: Standard number format. This is identical to the Rust string format.

§Low-Level Schema

This describes how to directly get and set flags from the NumberFormat packed struct. It is not recommended to use these directly, but for example, the following can be done:

use lexical_util::format;

assert_eq!(
    format::NumberFormatBuilder::new()
        .required_integer_digits(true)
        .build_strict(),
    format::STANDARD | format::REQUIRED_INTEGER_DIGITS
);

§Syntax Flags

Bitflags to get and set syntax flags for the format packed struct.

§Digit Separator Flags

Bitflags to get and set digit separators flags for the format packed struct.

§Character Shifts and Masks

Bitmasks and bit shifts to get and set control characters for the format packed struct.

§Character Functions

Functions to get control characters from the format packed struct.

  • digit_separator: Extract the digit separator from the format packed struct.
  • base_prefix: Extract the base prefix character from the format packed struct.
  • base_suffix: Extract the base suffix character from the format packed struct.
  • mantissa_radix: Extract the mantissa radix from the format packed struct.
  • exponent_base: Extract the exponent base from the format packed struct.
  • exponent_radix: Extract the exponent radix from the format packed struct.

§Validators

Functions to validate control characters for the format packed struct.

Structs§

NumberFormat
Helper to access features from the packed format struct.
NumberFormatBuilder
Validating builder for NumberFormat from the provided specifications.

Constants§

BASE_PREFIX
Mask to extract the base prefix character.
BASE_PREFIX_SHIFT
Shift to convert to and from a base prefix as a u8.
BASE_SUFFIX
Mask to extract the base suffix character.
BASE_SUFFIX_SHIFT
Shift to convert to and from a base suffix as a u8.
CASE_SENSITIVE_BASE_PREFIX
Base prefixes are case-sensitive.
CASE_SENSITIVE_BASE_SUFFIX
Base suffixes are case-sensitive.
CASE_SENSITIVE_EXPONENT
Exponent characters are case-sensitive.
CASE_SENSITIVE_SPECIAL
Special (non-finite) values are case-sensitive.
CONSECUTIVE_DIGIT_SEPARATOR
Multiple consecutive digit separators are allowed.
DIGIT_SEPARATOR
Mask to extract the digit separator character.
DIGIT_SEPARATOR_SHIFT
Shift to convert to and from a digit separator as a u8.
EXPONENT_BASE
Mask to extract the exponent base: the base the exponent is raised to.
EXPONENT_BASE_SHIFT
Shift to convert to and from an exponent base as a u32.
EXPONENT_CONSECUTIVE_DIGIT_SEPARATOR
Multiple consecutive exponent digit separators are allowed.
EXPONENT_INTERNAL_DIGIT_SEPARATOR
Digit separators are allowed between exponent digits.
EXPONENT_LEADING_DIGIT_SEPARATOR
A digit separator is allowed before any exponent digits.
EXPONENT_RADIX
Mask to extract the exponent radix: the radix for the exponent digits.
EXPONENT_RADIX_SHIFT
Shift to convert to and from an exponent radix as a u32.
EXPONENT_TRAILING_DIGIT_SEPARATOR
A digit separator is allowed after any exponent digits.
FRACTION_CONSECUTIVE_DIGIT_SEPARATOR
Multiple consecutive fraction digit separators are allowed.
FRACTION_INTERNAL_DIGIT_SEPARATOR
Digit separators are allowed between fraction digits.
FRACTION_LEADING_DIGIT_SEPARATOR
A digit separator is allowed before any fraction digits.
FRACTION_TRAILING_DIGIT_SEPARATOR
A digit separator is allowed after any fraction digits.
INTEGER_CONSECUTIVE_DIGIT_SEPARATOR
Multiple consecutive integer digit separators are allowed.
INTEGER_INTERNAL_DIGIT_SEPARATOR
Digit separators are allowed between integer digits.
INTEGER_LEADING_DIGIT_SEPARATOR
A digit separator is allowed before any integer digits.
INTEGER_TRAILING_DIGIT_SEPARATOR
A digit separator is allowed after any integer digits.
INTERNAL_DIGIT_SEPARATOR
Digit separators are allowed between digits.
LEADING_DIGIT_SEPARATOR
A digit separator is allowed before any digits.
MANTISSA_RADIX
Mask to extract the mantissa radix: the radix for the significant digits.
MANTISSA_RADIX_SHIFT
Shift to convert to and from a mantissa radix as a u32.
NO_EXPONENT_NOTATION
Exponent notation is not allowed.
NO_EXPONENT_WITHOUT_FRACTION
Exponent without a fraction component is not allowed.
NO_FLOAT_LEADING_ZEROS
Leading zeros before a float value are not allowed.
NO_INTEGER_LEADING_ZEROS
Leading zeros before an integer value are not allowed.
NO_POSITIVE_EXPONENT_SIGN
Positive sign before the exponent is not allowed.
NO_POSITIVE_MANTISSA_SIGN
Positive sign before the mantissa is not allowed.
NO_SPECIAL
Special (non-finite) values are not allowed.
RADIX
Alias for MANTISSA_RADIX.
RADIX_MASK
Mask to extract the exponent radix: the radix for the exponent digits.
RADIX_SHIFT
Alias for MANTISSA_RADIX_SHIFT.
REQUIRED_DIGITS
At least 1 digit in the number is required.
REQUIRED_EXPONENT_DIGITS
Digits are required after the exponent character. This check will only occur if the exponent character is present.
REQUIRED_EXPONENT_NOTATION
Exponent notation is required.
REQUIRED_EXPONENT_SIGN
Positive sign before the exponent is required.
REQUIRED_FRACTION_DIGITS
Digits are required after the decimal point. This check will only occur if the decimal point is present.
REQUIRED_INTEGER_DIGITS
Digits are required before the decimal point.
REQUIRED_MANTISSA_DIGITS
Mantissa digits are required (either before or after the decimal point).
REQUIRED_MANTISSA_SIGN
Positive sign before the mantissa is required.
SPECIAL_DIGIT_SEPARATOR
Any digit separators are allowed in special (non-finite) values.
STANDARD
Standard number format. This is identical to the Rust string format.
TRAILING_DIGIT_SEPARATOR
A digit separator is allowed after any digits.

Functions§

format_error
Get the error type from the format packed struct.
format_is_valid
Determine if the format packed struct is valid.
is_valid_base_prefix
Determine if the base prefix character is valid.
is_valid_base_suffix
Determine if the base suffix character is valid.
is_valid_digit_separator
Determine if the digit separator is valid.
is_valid_exponent_flags
Determine if the provided exponent flags are valid.
is_valid_punctuation
Determine if all of the “punctuation” characters are valid.
is_valid_radix
Determine if the radix is valid.