StringReplace

StringReplace["string",s->sp] replaces the string expression s by sp wherever it appears in "string". 

StringReplace["string",{s1->sp1,s2->sp2,…}] replaces the string expressions si by spi whenever they appear as substrings of "string".

StringReplace["string",srules,n] does only the first n replacements. 

StringReplace[{s1,s2,…},srules] gives the list of results for each of the si. 

StringReplace[srules] represents an operator form of StringReplace that can be applied to an expression.

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