Contents

# Expands variables in a template string. Variables are prefixed with a $ sign
# and consist of word characters (letters, digits, underscores). The name can
# be enclosed in curly braces to avoid unintended expansions. The $ sign can be
# escaped with a backslash (\), and backslashes can be escaped with another
# backslash. All occurrences of a variable in the string are replaced
#
# The str argument is the template string and the variables argument is a hash
# from variable name (Symbol) to variable value
#
# Note that the characters '\x00' and '\x01' are used internally and may not be
# present in the template string
#
def expand_variables(str, variables) # ChatGPT
  # Replace escaped bashslashes and dollar signs
  str = str.gsub('\\\\', "\x00").gsub('\\$', "\x01")
  
  # Expand variables
  str.gsub!(/\$(\w+)\b|\$\{(\w+)\}/) do |match| # Strange that '\b' is necessary
    key = ($1 || $2).to_sym
    variables[key] || match
  end

  # Restore escaped characters
  str.gsub("\x00", '\\').gsub("\x01", '$')
end

Version data entries

5 entries across 5 versions & 1 rubygems

Version	Path
prick-0.28.1	lib/ext/expand_variables.rb
prick-0.28.0	lib/ext/expand_variables.rb
prick-0.27.2	lib/ext/expand_variables.rb
prick-0.27.1	lib/ext/expand_variables.rb
prick-0.27.0	lib/ext/expand_variables.rb