Check that a document is valid TOML — toml

Runs the whole check phase of toml_parse() (the lexer, the grammar, the rules for defining tables and keys, every value, and the limits) without building any R value. It is exactly the check toml_parse() makes, with the same limits: the two disagree only where a document is valid TOML that R cannot hold, such as a string containing U+0000.

Usage

toml_validate(
  x,
  version = c("1.1.0", "1.0.0"),
  max_size = 64 * 1024^2,
  max_depth = 128L,
  max_items = 1e+06,
  max_string = 2^31 - 1,
  error = FALSE
)

Arguments

x: A TOML document: a single string, or a raw vector of UTF-8 bytes.
version: The TOML version to read: "1.1.0" (the default) or "1.0.0", which refuses the forms 1.1.0 added (\e and \xHH escapes, times without seconds, newlines and a trailing comma in inline tables).
max_size: The largest document accepted, in bytes, or Inf.
max_depth: The deepest nesting of tables and arrays, counting both; at most 1023.
max_items: The most keys plus array elements, or Inf.
max_string: The longest string or key, in decoded bytes, or Inf.
error: If FALSE (the default), return FALSE for a document that is not valid. If TRUE, raise the condition instead, so the caller learns why and where.

Value

TRUE when x is valid TOML within the limits. Otherwise FALSE, or with error = TRUE a condition of class zutoml_parse_error or zutoml_limit_error (see zutoml-conditions) carrying the line, column, byte offset and kind of the fault.

Examples

toml_validate('title = "TOML"\n[owner]\nname = "Tom"\n')
#> [1] TRUE
toml_validate("a = 1\na = 2\n")
#> [1] FALSE

# Why not, and where:
tryCatch(
  toml_validate("a = 1\na = 2\n", error = TRUE),
  zutoml_parse_error = function(e) c(e$kind, e$line, e$column)
)
#> [1] "duplicate_key" "2"             "1"