Top Level Namespace

Includes:
Constrain, ForwardTo, String::Text

Defined Under Namespace

Modules: Command, Fmt, FormatterOverrides, Prick, Timer Classes: IO, String

Instance Method Summary collapse

Instance Method Details

#expand_variables(str, variables) ⇒ Object

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 (String) to variable value

Note that the characters ‘x00’ and ‘x01’ are used internally and may not be present in the template string



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# File 'lib/prick/ext/expand_variables.rb', line 14

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
#   variables[key] || match
    variables[key] || ""
  end

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

#expand_variables?(str, variables) ⇒ Boolean

Return true if any of the variables will be expanded

Returns:

  • (Boolean) 


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# File 'lib/prick/ext/expand_variables.rb', line 30

def expand_variables?(str, variables)
  # Replace escaped bashslashes and dollar signs
  str = str.gsub('\\\\', "\x00").gsub('\\$', "\x01")

  # Look for expansion
  str.gsub!(/\$(\w+)\b|\$\{(\w+)\}/) do |match| # Strange that '\b' is necessary
    return true if variables.include?($1 || $2)
  end

  return false
end

#has_variables?(str) ⇒ Boolean

Return true if the string contains a variable

Returns:

  • (Boolean) 


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# File 'lib/prick/ext/expand_variables.rb', line 43

def has_variables?(str)
  # Replace escaped bashslashes and dollar signs
  str = str.gsub('\\\\', "\x00").gsub('\\$', "\x01")
  !(str =~ /\$[a-zA-Z{]/).nil?
end