Type:	Package
Title:	Scholarly and Academic Identifier Utilities
Version:	0.1.1
Language:	en-US
Description:	Detects, normalizes, classifies, and extracts scholarly identifier strings. Provides lightweight, dependency-free helpers for common identifier systems such as DOIs, ORCID iDs, ISBNs, ISSNs, arXiv identifiers, and PubMed identifiers. Functions are vectorized, predictable, and suitable as low-level building blocks for other R packages and data workflows. For online lookup, conversion, metadata retrieval, and linked identifier discovery, see 'scholidonline'.
License:	MIT + file LICENSE
URL:	https://thomas-rauter.github.io/scholid/, https://thomas-rauter.github.io/scholidonline/
BugReports:	https://github.com/Thomas-Rauter/scholid/issues
Depends:	R (≥ 3.5.0)
Suggests:	testthat (≥ 3.0.0), knitr (≥ 1.30), rmarkdown
Encoding:	UTF-8
RoxygenNote:	7.3.3
Config/testthat/edition:	3
VignetteBuilder:	knitr
NeedsCompilation:	no
Packaged:	2026-04-24 13:05:26 UTC; thomasrauter
Author:	Thomas Rauter [aut, cre, fnd]
Maintainer:	Thomas Rauter <rauterthomas0@gmail.com>
Repository:	CRAN
Date/Publication:	2026-04-24 13:40:02 UTC

Classify scholarly identifiers

Description

Performs best-guess classification of scholarly identifier strings. For each element of the input, the function returns the first matching identifier type, or NA_character_ if no supported type matches.

Classification is based on canonical identifier syntax. Wrapped forms (e.g., URLs or labels) should be normalized first with normalize_scholid().

Usage

classify_scholid(x)

Arguments

Value

A character vector of the same length as x, giving the detected identifier type for each element, or NA_character_ if no match is found.

Examples

classify_scholid(c("10.1000/182", "0000-0002-1825-0097", "not an id"))
classify_scholid(normalize_scholid("https://doi.org/10.1000/182", "doi"))

Detect scholarly identifier types

Description

Performs best-effort detection of scholarly identifier types from possibly wrapped identifier strings (e.g., URLs or labels).

For each element of the input, the function returns the first matching identifier type, or NA_character_ if no supported type matches.

Detection first attempts classification based on canonical identifier syntax (see classify_scholid()). If no match is found, the function attempts per-type normalization (see normalize_scholid()) and returns the first type for which normalization yields a non-missing result.

Use normalize_scholid() to convert detected values to canonical form once the identifier type is known.

Usage

detect_scholid_type(x)

Arguments

Value

A character vector of the same length as x, giving the detected identifier type for each element, or NA_character_ if no match is found.

See Also

classify_scholid(), normalize_scholid(), scholid_types()

Examples

detect_scholid_type(c(
  "https://doi.org/10.1000/182",
  "doi:10.1000/182",
  "https://orcid.org/0000-0002-1825-0097",
  "arXiv:2101.12345v2",
  "PMID: 12345678",
  "PMCID: PMC1234567",
  "not an id"
))

Extract scholarly identifiers from text

Description

Extract identifiers of a single supported type from free text.

The result is a list with one element per input element. Each element is a character vector of matches (possibly length 0). NA inputs yield an empty character vector.

Matches are returned as extracted identifier tokens from the text. Surrounding prose punctuation or markup fragments may be removed where necessary to isolate the identifier. Use normalize_scholid() to convert identifiers to canonical form.

Usage

extract_scholid(text, type)

Arguments

Value

A list of character vectors of extracted identifiers.

Examples

extract_scholid("See https://doi.org/10.1000/182.", "doi")
extract_scholid("ORCID 0000-0002-1825-0097", "orcid")

Test scholarly identifier validity

Description

Vectorized predicate that tests whether values are valid scholarly identifiers of a given supported type.

Validation is stricter than normalization. Values must conform to the canonical identifier syntax, and for identifier types with checksum algorithms (e.g., ORCID, ISBN, ISSN), checksum correctness is verified.

Inputs that are NA yield NA. Non-matching values return FALSE.

Use normalize_scholid() to convert structurally plausible identifiers to canonical form without performing checksum validation.

Usage

is_scholid(x, type)

Arguments

Value

A logical vector of the same length as x, indicating whether each element is a valid identifier of the specified type.

See Also

normalize_scholid(), scholid_types()

Examples

is_scholid("10.1000/182", "doi")
is_scholid("0000-0002-1825-0097", "orcid")

Normalize scholarly identifiers

Description

Vectorized normalizer that converts supported scholarly identifier values to a canonical form (e.g., removing URL prefixes, labels, or separators).

Normalization requires that inputs match the expected identifier structure. For identifier types with checksum algorithms, normalization also requires checksum-valid values. Inputs that do not meet these requirements yield NA_character_.

Normalized outputs are canonical, type-specific representations of valid identifiers.

Use is_scholid() to test whether values are fully valid identifiers, including checksum verification where applicable.

Usage

normalize_scholid(x, type)

Arguments

Value

A character vector with the same length as x. Invalid, checksum- failing, or structurally non-matching inputs yield NA_character_.

See Also

is_scholid(), scholid_types()

Examples

normalize_scholid("https://doi.org/10.1000/182", "doi")
normalize_scholid("https://orcid.org/0000-0002-1825-0097", "orcid")

Supported scholid identifier types

Description

Returns the set of identifier types supported by the scholid package.

Usage

scholid_types()

Value

A character vector of supported identifier type strings.

Examples

scholid_types()
"orcid" %in% scholid_types()