tabs spaces tabs

Last time i was able to come up with an algorithm to indent python code or basically code without  un-indent specifiers.  This time the challenge was tackling hanging indentation.

Now hanging indents in terms of word processing occur when all the lines except the first line are indented. In code terms it is something like this:

some_function(
    param1,
    param2,
    param3)

here param1, param2, param3 are indented while some_function is not.

Again the algorithm i use do hanging indentation is pretty straight forward, in simple terms it is:

  • Check if there is text to the right of paranthesis.
  • If there is, indent all lines till closing paranthesis that the column right after paranthesis.
  • Otherwise calculate the indentation relative to some_function and indent all later prams to that level.

This is the broad algorithm i use.

Though the difficult part was actually aligning in the file. N0w i align my files in the correct indentation levels(barring hanging indents) by:

  • remove all whitespaces to the left of every line.

I have a list called indentation_levels  which has indentation corresponding to line number, and also a variable insert which is either ‘\t’ or  tab_width*’ ‘  where tab_width is the number of spaces to indent

  • to each line add insert*indentation_level[line] to the left of the line.

basically line -> insert*indentation_level[line] + line .

now the problem was to insert absolute_indentation_levels in between normal indentation.

So whats the problem? just add number of spaces along with the normal spaces right? WRONG!

there’s a difference between

\t        \t
and 
        \t\t
are different

real life example:

class {
\tfunction(param1{
\t        \t do_something();}
\t         param2)
}

i was able to accomplish this by:

  • storing the previous indentation.of a block
  • then adding previous indent + hanging indent + indent level of that line.

do tell me if you find any fault in these algorithms, my work has recently been merged and can be found as the IndentationBear in the master branch of the coala-bears repositiory.

 

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