13. A computer program product comprising a non-transitory computer-readable storage medium storing computer program code that comprises: a source code file including computer code written in a host language, and inset computer code written in a domain specific language, the domain specific language being different from the host language; and a domain specific language specification including instructions written in the host language for executing the inset computer code in accordance with the domain specific language, the inset computer code being executed by relating tokens that include strings of characters from the domain specific language to corresponding tokens that include strings of characters from the host language and relating at least one grammatical rule for operations on tokens from the domain specific language to at least one corresponding grammatical rule for operations on tokens from the host language.
13. A computer program product comprising a non-transitory computer-readable storage medium storing computer program code that comprises: a source code file including computer code written in a host language, and inset computer code written in a domain specific language, the domain specific language being different from the host language; and a domain specific language specification including instructions written in the host language for executing the inset computer code in accordance with the domain specific language, the inset computer code being executed by relating tokens that include strings of characters from the domain specific language to corresponding tokens that include strings of characters from the host language and relating at least one grammatical rule for operations on tokens from the domain specific language to at least one corresponding grammatical rule for operations on tokens from the host language. 14. The computer program product of claim 13 , wherein the inset computer code comprises an escape token that indicates a start of the inset code in the domain specific language.