Write the message once. Get the C++.

`mstring` turns a file of messages — each with typed parameters and its text in every language — into the C++ that produces them: a string function, a streamable class, an exception class and its throw function, a fatal-error or a syslog function. A wrong argument is a compile error, not a garbled message; the texts are compiled in, so there is nothing to ship at run time. A command-line tool with a CMake function and a Conan recipe, MIT.

Typed parameters `@ count int` declares a parameter, `{$count}` puts it in the text — with stream formats if you want them, `{$size;std::fixed;precision(1)}`. The generated functions take real C++ types, so a wrong argument fails to compile instead of printing the wrong thing.

Every language in one place A `[tr]` header starts the Turkish text of a message. The generated code picks the text from the locale: `[tr]` matches `tr_TR.UTF-8`, the most specific language wins, the default text is the fallback. mstring warns about a message missing a language, or a parameter one translation forgot.

Errors as first-class messages One message becomes an exception class that stores its parameters and implements `what()`, a `[[noreturn]]` throw function, a fatal-error function or a syslog call. `$EXPORT` and `$EXCEPTION OVERRIDE` fit it into a shared library's own exception hierarchy — plugin's `dsold` generates its exceptions this way.

CMake, Conan, C++17 `mstring_generate(GEN messages.msg)` runs the generator at build time and only rewrites a file when it changes. Conan: `tool_requires("mstring/[>=1.3 <2]")`. The generated code builds with C++17 or later and `-Wall -Wextra -Werror`; string functions are several times faster than an `ostringstream`.