XMLStarlet - XMLStarlet Command Line XML Toolkit
Gema - General purpose text macro processor.
xmllint - command line XML tool
GPP - GPP is a general-purpose preprocessor with customizable syntax, suitable for a wide range of...
GNU sed - sed (stream editor) is a Unix utility that parses text and implements a programming language which...
Bracmat - Programming language for symbolic computation with extraordinary combination of pattern matching...