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Unix shell if statement explained

Pat Brisbin gives one of the most approachable explanations of the Unix shell's if statement that I've seen.

if [ "string" != "other string" ]; then
  # same as if test "string" != "other string"; then

Unfortunately, many users come across this usage first and assume the brackets are part of if itself. This can lead to some nonsensical statements.

I will always hold my nose every time I type fi, but I've grown more fond of shell scripting the last few years.

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