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Parameter Expansion Default And Substitute

Use bash parameter expansion for default values, substring extraction, and pattern removal in a single script.

BashConfig Management

Code

snippet
#!/usr/bin/env bash
set -euo pipefail

INPUT="${1:-default_value}"
SUFFIX="${2:-txt}"

echo "Input: ${INPUT}"
echo "First 4 chars: ${INPUT:0:4}"

FILENAME="archive.tar.gz"
echo "Without extension: ${FILENAME%%.*}"
echo "Last extension: ${FILENAME##*.}"
echo "Upper: ${INPUT^^}"
echo "Length: ${#INPUT}"

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