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crunch (version 1.30.4)

buildDelimRegex: Build Regex to find delimited items.

Description

A delimited item maple can appear in a list in four ways

  1. At the start of a list maple; oak

  2. In the middle of a list oak; maple; birch

  3. At the end of a list oak; maple

  4. Alone with no delimiters maple

Usage

buildDelimRegex(str, delim)

Value

A character string

Arguments

str

A string whose presence indicates a selection

delim

The delimiter separating the responses

Details

This function builds a regex expression which captures those four cases It is mostly broken out of createSubvarDeriv() for testing purposes.