Wrappers around to_any_case()

to_snake_case(string, abbreviations = NULL, sep_in = "[^[:alnum:]]",
  parsing_option = 1, transliterations = NULL, numerals = "middle",
  sep_out = NULL, unique_sep = NULL, empty_fill = NULL,
  prefix = "", postfix = "")

to_lower_camel_case(string, abbreviations = NULL,
  sep_in = "[^[:alnum:]]", parsing_option = 1,
  transliterations = NULL, numerals = "middle", sep_out = NULL,
  unique_sep = NULL, empty_fill = NULL, prefix = "", postfix = "")

to_upper_camel_case(string, abbreviations = NULL,
  sep_in = "[^[:alnum:]]", parsing_option = 1,
  transliterations = NULL, numerals = "middle", sep_out = NULL,
  unique_sep = NULL, empty_fill = NULL, prefix = "", postfix = "")

to_screaming_snake_case(string, abbreviations = NULL,
  sep_in = "[^[:alnum:]]", parsing_option = 1,
  transliterations = NULL, numerals = "middle", sep_out = NULL,
  unique_sep = NULL, empty_fill = NULL, prefix = "", postfix = "")

to_parsed_case(string, abbreviations = NULL, sep_in = "[^[:alnum:]]",
  parsing_option = 1, transliterations = NULL, numerals = "middle",
  sep_out = NULL, unique_sep = NULL, empty_fill = NULL,
  prefix = "", postfix = "")

to_mixed_case(string, abbreviations = NULL, sep_in = "[^[:alnum:]]",
  parsing_option = 1, transliterations = NULL, numerals = "middle",
  sep_out = NULL, unique_sep = NULL, empty_fill = NULL,
  prefix = "", postfix = "")

to_lower_upper_case(string, abbreviations = NULL,
  sep_in = "[^[:alnum:]]", parsing_option = 1,
  transliterations = NULL, numerals = "middle", sep_out = NULL,
  unique_sep = NULL, empty_fill = NULL, prefix = "", postfix = "")

to_upper_lower_case(string, abbreviations = NULL,
  sep_in = "[^[:alnum:]]", parsing_option = 1,
  transliterations = NULL, numerals = "middle", sep_out = NULL,
  unique_sep = NULL, empty_fill = NULL, prefix = "", postfix = "")

to_swap_case(string, abbreviations = NULL, sep_in = "[^[:alnum:]]",
  parsing_option = 1, transliterations = NULL, numerals = "middle",
  sep_out = NULL, unique_sep = NULL, empty_fill = NULL,
  prefix = "", postfix = "")

to_sentence_case(string, abbreviations = NULL, sep_in = "[^[:alnum:]]",
  parsing_option = 1, transliterations = NULL, numerals = "middle",
  sep_out = NULL, unique_sep = NULL, empty_fill = NULL,
  prefix = "", postfix = "")

to_random_case(string, abbreviations = NULL, sep_in = "[^[:alnum:]]",
  parsing_option = 1, transliterations = NULL, numerals = "middle",
  sep_out = NULL, unique_sep = NULL, empty_fill = NULL,
  prefix = "", postfix = "")

to_title_case(string, abbreviations = NULL, sep_in = "[^[:alnum:]]",
  parsing_option = 1, transliterations = NULL, numerals = "middle",
  sep_out = NULL, unique_sep = NULL, empty_fill = NULL,
  prefix = "", postfix = "")

Arguments

string

A string (for example names of a data frame).

abbreviations

character. (Case insensitive) matched abbreviations are surrounded by underscores. In this way, they can get recognized by the parser. This is useful when e.g. parsing_option 1 is needed for the use case, but some abbreviations but some substrings would require parsing_option 2. Furthermore, this argument also specifies the formatting of abbreviations in the output for the cases title, mixed, lower and upper camel. E.g. for upper camel the first letter is always in upper case, but when the abbreviation is supplied in upper case, this will also be visible in the output.

Use this feature with care: One letter abbreviations and abbreviations next to each other are hard to read and also not easy to parse for further processing.

sep_in

(short for separator input) if character, is interpreted as a regular expression (wrapped internally into stringr::regex()). The default value is a regular expression that matches any sequence of non-alphanumeric values. All matches will be replaced by underscores (additionally to "_" and " ", for which this is always true, even if NULL is supplied). These underscores are used internally to split the strings into substrings and specify the word boundaries.

parsing_option

An integer that will determine the parsing_option.

  • 1: "RRRStudio" -> "RRR_Studio"

  • 2: "RRRStudio" -> "RRRS_tudio"

  • 3: "RRRStudio" -> "RRRSStudio". This will become for example "Rrrstudio" when we convert to lower camel case.

  • -1, -2, -3: These parsing_options's will suppress the conversion after non-alphanumeric values.

  • 0: no parsing

transliterations

A character vector (if not NULL). The entries of this argument need to be elements of stringi::stri_trans_list() (like "Latin-ASCII", which is often useful) or names of lookup tables (currently only "german" is supported). In the order of the entries the letters of the input string will be transliterated via stringi::stri_trans_general() or replaced via the matches of the lookup table. When named character elements are supplied as part of `transliterations`, anything that matches the names is replaced by the corresponding value. You should use this feature with care in case of case = "parsed", case = "internal_parsing" and case = "none", since for upper case letters, which have transliterations/replacements of length 2, the second letter will be transliterated to lowercase, for example Oe, Ae, Ss, which might not always be what is intended. In this case you can make usage of the option to supply named elements and specify the transliterations yourself.

numerals

A character specifying the alignment of numerals ("middle", left, right or asis). I.e. numerals = "left" ensures that no output separator is in front of a digit.

sep_out

(short for separator output) String that will be used as separator. The defaults are "_" and "", regarding the specified case. When length(sep_out) > 1, the last element of sep_out gets recycled and separators are incorporated per string according to their order.

unique_sep

A string. If not NULL, then duplicated names will get a suffix integer in the order of their appearance. The suffix is separated by the supplied string to this argument.

empty_fill

A string. If it is supplied, then each entry that matches "" will be replaced by the supplied string to this argument.

prefix

prefix (string).

postfix

postfix (string).

Value

A character vector according the specified parameters above.

A character vector according the specified target case.

Note

caseconverters are vectorised over string, sep_in, sep_out, empty_fill, prefix and postfix.

See also

snakecase on github, to_any_case for flexible high level conversion and more examples.

Examples

strings <- c("this Is a Strange_string", "AND THIS ANOTHER_One", NA) to_snake_case(strings)
#> [1] "this_is_a_strange_string" "and_this_another_one" #> [3] NA
to_lower_camel_case(strings)
#> [1] "thisIsAStrangeString" "andThisAnotherOne" NA
to_upper_camel_case(strings)
#> [1] "ThisIsAStrangeString" "AndThisAnotherOne" NA
to_screaming_snake_case(strings)
#> [1] "THIS_IS_A_STRANGE_STRING" "AND_THIS_ANOTHER_ONE" #> [3] NA
to_lower_upper_case(strings)
#> [1] "thisISaSTRANGEstring" "andTHISanotherONE" NA
to_upper_lower_case(strings)
#> [1] "THISisAstrangeSTRING" "ANDthisANOTHERone" NA
to_parsed_case(strings)
#> [1] "this_Is_a_Strange_string" "AND_THIS_ANOTHER_One" #> [3] NA
to_mixed_case(strings)
#> [1] "this_Is_a_Strange_string" "And_This_Another_One" #> [3] NA
to_swap_case(strings)
#> [1] "THIS iS A sTRANGE_STRING" "and this another_oNE" #> [3] NA
to_sentence_case(strings)
#> [1] "This is a strange string" "And this another one" #> [3] NA
to_random_case(strings)
#> [1] "THiS iS A sTRANgE_stRInG" "ANd thIS anOThER_OnE" #> [3] "NA"
to_title_case(strings)
#> [1] "This is a Strange String" "And this Another One" #> [3] NA