what is the command-line processing order for string operators like ${string#patten} in bash shell? -


i learning command-line processing of bash shell. understand process of substituting value common parameter $para or ${para}. question processing order when string operator involved. example, if para variable preceded tab followed "string". known ${para#\t} meant delete preceding tab in para. how processed shell? there command substitution involved?

can give hint? thank you.


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