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Top Forums Shell Programming and Scripting Bash: if condition as variable Post 302397020 by Franklin52 on Saturday 20th of February 2010 12:07:47 PM
Old 02-20-2010
Use the eval command and build the condition string as:
Code:
condition="[ $a = $b -o  $a = $a -o  $c = $a ]"

if eval "$condition"
then 
  echo "true"
else 
  echo "false"
fi

 

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IS_STRING(3)								 1							      IS_STRING(3)

is_string - Find whether the type of a variable is string

SYNOPSIS
bool is_string (mixed $var) DESCRIPTION
Finds whether the type given variable is string. PARAMETERS
o $var - The variable being evaluated. RETURN VALUES
Returns TRUE if $var is of type string, FALSE otherwise. EXAMPLES
Example #1 is_string(3) example <?php $values = array(false, true, null, 'abc', '23', 23, '23.5', 23.5, '', ' ', '0', 0); foreach ($values as $value) { echo "is_string("; var_export($value); echo ") = "; echo var_dump(is_string($value)); } ?> The above example will output: is_string(false) = bool(false) is_string(true) = bool(false) is_string(NULL) = bool(false) is_string('abc') = bool(true) is_string('23') = bool(true) is_string(23) = bool(false) is_string('23.5') = bool(true) is_string(23.5) = bool(false) is_string('') = bool(true) is_string(' ') = bool(true) is_string('0') = bool(true) is_string(0) = bool(false) SEE ALSO
is_float(3), is_int(3), is_bool(3), is_object(3), is_array(3). PHP Documentation Group IS_STRING(3)
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