Creating a Custom File Parser

Perhaps you would like to DRY some redundant code in your source?

Or simply make a little shortcut, e.g. something like !fn or !command?

Here is how you would configure caseEsac to replace every instance of "foo" in your code with "FOO BAR":

Create a Processor

foo-converter.sh

#! /bin/bash

# $1 This is the text of a file being parsed
echo "$1" | sed 's/foo/FOO BAR/g'

Now register it with caseEsac

./caseEsac compile --src src/ --out cmd.sh -p foo-converter

That’s it!

Every file will be run through your processor.

Available Variables

When processors are run, these environment variables are available:

$VARIABLE	Description
$CASE_ESAC_SOURCE_ROOT_PATH	The input path specified by --src
$CASE_ESAC_OUTPUT_FILE_PATH	The output path specified by --out
$CASE_ESAC_FUNCTION_NAME	The name of the function (inferred from --out or provided via --fn)
$CASE_ESAC_FULL_COMMAND_NAME	The full command name associated with the file being parsed, e.g. myCommand greetings hello (note: this includes the top-level function name)
$CASE_ESAC_SOURCE_FILE_PATH	The full path of the current file being parsed
$CASE_ESAC_SOURCE_RELATIVE_FILE_PATH	The path of the current file being parsed relative to the root output path being compiled
$CASE_ESAC_FILE_PROCESSOR	The binary or function name of the current processor being run

Parsing One Line at a Time

You might find this sample useful if you want to parse each line of a file, looking for a particular pattern!

foo-converter.sh

#! /bin/bash

soureCodeToReturn=""

while IFS="" read -r line || [ -n "$line" ]
do
  if [[ "$line" =~ ^(some)-(pattern)$ ]]
  then
    # Extract matches from the line
    interestingPart="${BASH_REMATCH[1]}"
    # Replace this line of code with something interesting
    sourceCodeToReturn+="Some code $interestingPart"
  else
    # Nothing interesting, 'skip' this line
    sourceCodeToReturn+="$line"
  fi
done < <( printf '%s' "$1" )

printf '%s' "$sourceCodeToReturn"