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<?php $camelCase = "USADollarSymbol"; echo strtolower( preg_replace( ["/([A-Z]+)/", "/_([A-Z]+)([A-Z][a-z])/"], ["_$1", "_$1_$2"], lcfirst($camelCase) ) );
Output for 7.1.25 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
u_sa_dollar_symbol

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143.98 ms | 407 KiB | 5 Q