Method: Janeway::Functions#parse_function_search

Defined in:
lib/janeway/functions/search.rb

#parse_function_search ⇒ Object

2.4.7. search() Function Extension Parameters:

1. ValueType (string)
2. ValueType (string conforming to [RFC9485])

Result:

LogicalType

The search() function extension provides a way to check whether a given string contains a substring that matches a given regular expression, which is in the form described in [RFC9485].

$[?search(@.author, “[BR]ob”)]

Its arguments are instances of ValueType (possibly taken from a singular query, as for the first argument in the example above). If the first argument is not a string or the second argument is not a string conforming to [RFC9485], the result is LogicalFalse. Otherwise, the string that is the first argument is searched for a substring that matches the I-Regexp contained in the string that is the second argument; the result is LogicalTrue if at least one such substring exists and is LogicalFalse otherwise.

tl;dr: How is this different from the match function? “match” must match the entire string, “search” matches a substring.

Raises:



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# File 'lib/janeway/functions/search.rb', line 30

def parse_function_search
  consume # function
  raise "expect group_start token, found #{current}" unless current.type == :group_start

  consume # (

  # Read first parameter
  parameters = []
  parameters << parse_function_parameter
  raise Error, 'Insufficient parameters for search() function call' unless current.type == :union

  consume # ,

  # Read second parameter (the regexp)
  # This could be a string, in which case it is available now.
  # Otherwise it is an expression that takes the regexp from the input document,
  # and the iregexp will not be available until interpretation.
  parameters << parse_function_parameter
  raise Error, 'Too many parameters for match() function call' unless current.type == :group_end

  AST::Function.new('search', parameters) do |str, str_iregexp|
    if str.is_a?(String) && str_iregexp.is_a?(String)
      regexp = translate_iregex_to_ruby_regex(str_iregexp, anchor: false)
      regexp.match?(str)
    else
      false # result defined by RFC9535
    end
  end
end