Struct stringsext::mission::Utf8Filter

pub struct Utf8Filter {
    pub af: u128,
    pub ubf: u64,
    pub grep_char: Option<u8>,
}

When the decoder finds a valid Unicode character, it decodes it into UTF-8. The leading byte of this UTF-8 multi-byte-character must then pass an additional filter before being printed: the so called Utf8Filter. It comes with three independant filter criteria:

1. The Ascii-Filter Utf8Filter::asf,
2. the Unicode-block-filter Utf8Filter::ubf,
3. and the Utf8::must_hame-filter.

The Ascii-Filter Utf8Filter::asf and the Unicode-block-filter Utf8Filter::ubf are implemented by the Utf8Filter::pass_filter() function. The Utf8::grep_char-filter is implemented by the helper::SplitStr::next() iterator function.

Fields

af: u128

Every bit 0..=127 of the Utf8Filer::af filter parameter maps to one ASCII-code-position 0x00..=0x7F that is checked by pass_filter() against the UTF-8 leading byte of the incoming stream. For example if the leading byte’s code is 32 and the Utf8Filter::af has bit number 32 set, then the character passes the filter. If not, it is rejected.

ubf: u64

Every bit 0..=63 maps to one leading-byte’s code position 0xC0..0xFF, e.g. bit 0 is set -> all characters with leading byte 0xC0 pass the filter, If bit 1 is set -> all characters with all leading byte 0xC1, … pass the filter. Otherwise, the character is rejected.

grep_char: Option<u8>

If Some(), a finding must have at least one leading byte equal to the grep_char ASCII code. This is useful when you grep for path-strings: e.g. “0x2f” or “0x5c”.

Implementations

impl Utf8Filter

pub fn pass_af_filter(&self, b: u8) -> bool

This function applies the Ascii-Filter Utf8Filter::asf to the UTF-8 leading byte b. It assumes that b<=0x7f!

pub fn pass_ubf_filter(&self, b: u8) -> bool

This function applies the Unicode-Block-Filter Utf8Filter::ubf to the UTF-8 leading byte b. It assumes that b>0x7f!

Trait Implementations

impl Clone for Utf8Filter

fn clone(&self) -> Utf8Filter

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Utf8Filter

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

Formats the value using the given formatter.

impl Ord for Utf8Filter

Needed for merging.

fn cmp(&self, other: &Self) -> 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 + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq for Utf8Filter

fn eq(&self, other: &Utf8Filter) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

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

impl PartialOrd for Utf8Filter

Needed for merging.

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

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

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

This method tests less than (for self and other) and is used by the < operator.

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

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

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

This method tests greater than (for self and other) and is used by the > operator.

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

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

impl Copy for Utf8Filter

impl Eq for Utf8Filter

impl StructuralPartialEq for Utf8Filter