Description:
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The php_filter_float function located in /[svn]/php/php-src/trunk/ext/filter/logical_filters.c does not allow setting custom thousand separators - the function always uses built-in set of three separators provided in the tsd_sep[3] local variable, currently ",.'" (without double quotes).

As a result, the function is not usable in countries which uses other char as a thousand separator, for example " ". Additionally, it does not allow to prohibit separators some of the separators.

Please add support for setting custom thousand separators which will override the one built-in in the source code.

Test script:
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var_dump(filter_var('1 000', FILTER_VALIDATE_FLOAT, array('flags' => FILTER_FLAG_ALLOW_THOUSAND, 'options' => array('thousand' => ' '))));

Expected result:
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float(1000)

Actual result:
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bool(false)