Match.groups

Declaration and parameters

사용 조건

기본 포함 · 미정

Import std.regex in language mode 5.21.

The current compiler selects std/regex.tpz for this language mode. Availability in other released editions and inclusion in each installed distribution are Pending.

수신자

Match

매개변수 제약

추가 계약은 미정입니다.

Match.start and Match.end are read-only nonnegative UTF-8 byte offsets in the original input. They follow the inclusive start and exclusive end of byte intervals. Both are scalar boundaries and the end does not exceed the UTF-8 byte length of the input.

Match.text is the matched substring. An empty match has equal start and end and an empty text value. The offsets are not string grapheme indexes. A match may select a combining mark inside a grapheme.

Encoding the original input with encodeUtf8, slicing its bytes from start to end, and calling decodeUtf8 returns Ok containing Match.text. This relationship also holds for non-ASCII input.

Match.groups returns an independent array indexed by capture number. Entry zero is Some containing the entire match. Capturing parentheses are numbered from one in opening-parenthesis order. Named groups participate in the same numbering and noncapturing groups do not.

A nonparticipating capture has value None(). A participating empty capture has value Some containing an empty string. A repeated capture retains the last participating capture in the selected match.

Match.named returns an independent map from capture names to captured strings. A nonparticipating named capture is absent. A participating empty named capture is present with an empty string. Names are inserted in ascending ASCII order.

Reading a Match field evaluates its receiver once and does not modify the Match or input. Mutating a groups array or named map does not affect a later field read. Field access cannot fail for a Match value.

결과

추가 계약은 미정입니다.

The declared result type is Array<Option<string>>.

효과

미정

실패

미정

Result and effects

링크

Select this field from a value of its named type without call parentheses.

An independent array of optional numbered captures beginning with the complete match at zero.

Resolved contracts

링크

std.regex →

Read match boundaries and capture snapshots

링크

규칙topaz.stdlib.contract.regex-match.rule

Read match boundaries and capture snapshots

Match.start and Match.end are read-only nonnegative UTF-8 byte offsets in the original input. They follow the inclusive start and exclusive end of byte intervals. Both are scalar boundaries and the end does not exceed the UTF-8 byte length of the input.

Match.text is the matched substring. An empty match has equal start and end and an empty text value. The offsets are not string grapheme indexes. A match may select a combining mark inside a grapheme.

Encoding the original input with encodeUtf8, slicing its bytes from start to end, and calling decodeUtf8 returns Ok containing Match.text. This relationship also holds for non-ASCII input.

Match.groups returns an independent array indexed by capture number. Entry zero is Some containing the entire match. Capturing parentheses are numbered from one in opening-parenthesis order. Named groups participate in the same numbering and noncapturing groups do not.

A nonparticipating capture has value None(). A participating empty capture has value Some containing an empty string. A repeated capture retains the last participating capture in the selected match.

Match.named returns an independent map from capture names to captured strings. A nonparticipating named capture is absent. A participating empty named capture is present with an empty string. Names are inserted in ascending ASCII order.

Reading a Match field evaluates its receiver once and does not modify the Match or input. Mutating a groups array or named map does not affect a later field read. Field access cannot fail for a Match value.

이유

Byte offsets identify every exact match even when a pattern selects part of a grapheme. The byte-slice relationship makes those offsets usable without confusing them with text indexing. Optional numbered captures and omitted named entries distinguish absence from a captured empty string.

예제 Report UTF-8 byte offsets for non-ASCII matches →Recover a match through the byte slice identified by its offsets →Keep capture zero and distinguish missing and empty captures →Omit absent named captures and retain a captured empty string →

Report UTF-8 byte offsets for non-ASCII matches

링크

run · running · 검증 · 미실행

main.tpzReport UTF-8 byte offsets for non-ASCII matches플레이그라운드 열기 →

import std.regex { Regex }
import std.io
function show(patternText: string, text: string) -> () {
match (Regex.compile(patternText)) {
case Ok(pattern) => {
match (pattern.find(text)) {
case Some(found) => io.writeLine("{found.start}:{found.end}:{found.text}")
case None() => io.writeLine("no match")
}
}
case Err(_) => io.writeLine("compile failed")
}
}
show("한", "é한🙂")
show("́", "éx")

기대 출력종료 코드 0

2:5:한
1:3:́

$ topaz run main.tpz · 대상 제품 5.21.3

기대 결과

실행을 마칩니다. 종료 코드 0.

표준 오류 출력 없음.

기대 표준 출력

2:5:한
1:3:́

이 예제는 아직 실행하지 않았습니다.

Recover a match through the byte slice identified by its offsets

링크

run · running · 검증 · 미실행

main.tpzRecover a match through the byte slice identified by its offsets플레이그라운드 열기 →

import std.regex { Regex }
import std.io
let text = "한x"
match (Regex.compile("한")) {
case Ok(pattern) => {
match (pattern.find(text)) {
case Some(found) => {
let bytes = text.encodeUtf8().slice(found.start, found.end)
match (bytes.decodeUtf8()) {
case Ok(decoded) => io.writeLine(decoded)
case Err(_) => io.writeLine("invalid UTF-8 slice")
}
}
case None() => io.writeLine("no match")
}
}
case Err(_) => io.writeLine("compile failed")
}

기대 출력종료 코드 0

한

$ topaz run main.tpz · 대상 제품 5.21.3

기대 결과

실행을 마칩니다. 종료 코드 0.

표준 오류 출력 없음.

기대 표준 출력

한

이 예제는 아직 실행하지 않았습니다.

Keep capture zero and distinguish missing and empty captures

링크

run · running · 검증 · 미실행

main.tpzKeep capture zero and distinguish missing and empty captures플레이그라운드 열기 →

import std.regex { Regex }
import std.io
match (Regex.compile("(?<word>a)(b)?()")) {
case Ok(pattern) => {
match (pattern.find("a")) {
case Some(found) => {
io.writeLine("{found.groups.length}")
for group in (found.groups) {
match (group) {
case Some(text) => io.writeLine("some={text}")
case None() => io.writeLine("none")
}
}
}
case None() => io.writeLine("no match")
}
}
case Err(_) => io.writeLine("compile failed")
}

기대 출력종료 코드 0

4
some=a
some=a
none
some=

$ topaz run main.tpz · 대상 제품 5.21.3

기대 결과

실행을 마칩니다. 종료 코드 0.

표준 오류 출력 없음.

기대 표준 출력

4
some=a
some=a
none
some=

이 예제는 아직 실행하지 않았습니다.

Omit absent named captures and retain a captured empty string

링크

run · running · 검증 · 미실행

main.tpzOmit absent named captures and retain a captured empty string플레이그라운드 열기 →

import std.regex { Regex }
import std.io
match (Regex.compile("(?<z>a)?(?<a>b*)")) {
case Ok(pattern) => {
match (pattern.find("")) {
case Some(found) => {
let mut snapshot = found.named
let hasOptional = snapshot.containsKey("z")
io.writeLine("{hasOptional}")
match (snapshot.get("a")) {
case Some(text) => io.writeLine("some={text}")
case None() => io.writeLine("none")
}
snapshot.insert("a", "changed")
match (found.named.get("a")) {
case Some(text) => io.writeLine("again={text}")
case None() => io.writeLine("none")
}
}
case None() => io.writeLine("no match")
}
}
case Err(_) => io.writeLine("compile failed")
}

기대 출력종료 코드 0

false
some=
again=

$ topaz run main.tpz · 대상 제품 5.21.3

기대 결과

실행을 마칩니다. 종료 코드 0.

표준 오류 출력 없음.

기대 표준 출력

false
some=
again=

이 예제는 아직 실행하지 않았습니다.

문서 검색

Match.groups

Declaration and parameters

사용 조건

수신자

매개변수 제약

결과

효과

실패

Result and effects

Resolved contracts

Read match boundaries and capture snapshots

Read match boundaries and capture snapshots

이유

Report UTF-8 byte offsets for non-ASCII matches

기대 결과

Recover a match through the byte slice identified by its offsets

기대 결과

Keep capture zero and distinguish missing and empty captures

기대 결과

Omit absent named captures and retain a captured empty string

기대 결과

메뉴

Declaration and parameters

사용 조건

수신자

매개변수 제약

결과

효과

실패

Result and effects

Resolved contracts

Related entries

Read match boundaries and capture snapshots

Read match boundaries and capture snapshots

이유

Report UTF-8 byte offsets for non-ASCII matches

기대 결과

Recover a match through the byte slice identified by its offsets

기대 결과

Keep capture zero and distinguish missing and empty captures

기대 결과

Omit absent named captures and retain a captured empty string

기대 결과