[FR-devel] Thoughts on refactoring

[Hal E. Fulton]

Here are some miscellaneous thoughts.

Disclaimer: I've never used a real IDE
that did automatic refactoring.

I did long ago play with a tool called
Alice Pascal (ca. 1985) which was years
ahead of its time in many ways.

It seems to me that there are at least
two kinds of refactoring:
1. Global stuff, like change the name
of this method everywhere, etc.
2. Local stuff, like change the nature
of this piece of code in a highly 
specific way.

By the way, I think many of the items
from the Fowler book will be applicable,
in addition to the ones someone pasted
into the wiki from the Java tool.

Some examples of #2 above:

a. I'd like to be able to highlight a 
group of lines and apply an operation
to protect it by catching exceptions
(leaving blanks for me to fill in).

  foo()
  bar()
  bam()
# becomes...
  begin
    foo()
    bar()
    bam()
  rescue
  end

b. I'd like to be able to transform 
control structures into equivalent
code using different structures (tests,
loops, ...) For example, I wish I had 
used a case instead of an if:

  if x==1
    foo()
  elsif x==2
    bar()
  else
    bam()
  end
# becomes...
  case x
    when 1
      foo()
    when 2
      bar()
  else
    bam() 
  end

c. One thing I sometimes find myself doing 
is converting to (and from) multiple assignment
form. I'd like to be able to highlight
   a=1
   b=2
   c=3
# and have it become
   a, b, c = 1, 2, 3
# or vice versa

Just some more thoughts.

Hal