Built-in Mathematica Symbol

StringPosition

StringPosition["string", "sub"]
gives a list of the starting and ending character positions at which "sub" appears as a substring of "string".

StringPosition["string", patt]
gives all positions at which substrings matching the general string expression patt appear in "string".

StringPosition["string", patt, n]
includes only the first n occurrences of patt.

StringPosition["string", {patt₁, patt₂, ...}]
gives positions of all the patt_i.

StringPosition[{s₁, s₂, ...}, p]
gives the list of results for each of the s_i.

The string expression patt can contain any of the objects specified in the notes for StringExpression.

With the default option setting Overlaps->True, StringPosition includes substrings that overlap. With the setting Overlaps->False such substrings are excluded. »

With Overlaps->All, multiple substrings that match the same string expression are all included. With Overlaps->True, only the first such matching substring at a given position is included. »