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>>>>> On Sun, 12 Jun 2016, Benda Xu wrote: |
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>> Inside [[ ]] quotes are generally not needed. (There are several other |
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>> instances of this.) |
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> I thought so too, but with an experiment: |
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> bash --version |
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> GNU bash, version 4.3.30(1)-release (x86_64-pc-linux-gnu) |
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> bash -l |
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> $ [[ -f a b ]] && echo hi |
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> bash: syntax error in conditional expression |
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> bash: syntax error near `b' |
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> $ [[ -f "a b" ]] && echo hi |
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> hi |
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Wrong experiment, so you get wrong results. :) |
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$ foo="a b" |
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$ [[ -f ${foo} ]] && echo yes || echo no |
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no |
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$ touch "a b" |
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$ [[ -f ${foo} ]] && echo yes || echo no |
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yes |
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> So it seems that [[ ]] does need quotes. |
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I doesn't around a variable. |
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Ulrich |
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