The execution character set supplies the implementation-defined characters and numeric encodings used while a C program executes. Numeric character escapes therefore depend on the platform and execution setting. section 8.4
A hexadecimal escape can consume the next character
The string "\xdeBruyn" is parsed differently from "\xde" "Bruyn": the hexadecimal escape consumes the B, producing one encoded character followed by "ruyn". Consecutive string literals avoid that ambiguity. TAKEAWAY: numerically encoded characters are not fully portable and should generally be avoided. section 8.4
Character conversion exposes further assumptions about the execution character set:
- The hexatridecimal example assumes lowercase letters are contiguous and that uppercase and lowercase letters have a suitable relationship; those assumptions require testing or removal for portability. section 8.4
