Selecting words in the beginning of a LINE (not a paragraph)

Question

Hi
I'm trying to avoid certain combinations to fall at the beginning of any line in a body text.
How do I select a particular character only if it occurs in the beginning of a line (but in the middle of a paragraph.
For instance I want to select the char "a" only if it occurs at the left margin of a column
I only find the location marc "beginning of a paragraph" (^), or beginning of a word,  but not the beginning of a line.
It could be as grep, or as a script.
Anybody?
Thank you
/javier

Answer 1

It would need a script. GREP is not aware of the individual lines in a paragraph.
The good news is, InDesign's scripting language is fully aware of lines. There are, on first sight, two possible ways of locating all a's at the start of a line. Either search for all a's (doesn't need a GREP, but you must remember to set caseSensitive in the FindChangePreferences) and loop over them, checking for the ones that are at the start of a line, or check all lines one by one, checking for the ones that start with an 'a'.
Both options seem equally slow I guess what to use depends on your text, and what you'd want to do when one is found. On that note: you must process them from last found to first, because if you change something, it may have an effect on all text that follows.