var_export must return legal php code, that is to say, the code returned by var_export can be directly assigned to a variable as a php code. And this variable will get the same type of value as var_export
Problem discovery
When tracking yratings_get_targets,
error_log (var_export(yblog_mspconfiginit("ratings"),true)); always prints out that the return value of yblog_mspconfiginit("ratings") is NULL
, which leads me to think that the connection to the DB cannot be established, which is wrong. Been on the road for a day.
Finally I discovered that this is one of the differences between var_export and var_dump
This is:
Cause of the problem
var_export must return legal PHP code, that is to say, the code returned by var_export can be directly assigned to a variable as PHP code. And this variable will get the same type of value as var_export
However, when the variable type is resource, it cannot be simply copycopied, so , When the variable of var_export is of resource type, var_export will return NULL
Instance
$res = yblog_mspconfiginit("ratings"); var_dump($res); var_export($res);结果: resource(1) of type (yahoo_yblog) NULL再比如: $res = fopen('status.html', 'r'); var_dump($res); var_export($res);结果: resource(2) of type (stream) NULL
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