Coding conventions

Naming and structural conventions followed across mist-hep. Reference material for new contributors and code review — not a discussion log. These conventions are inherited verbatim from mist; only the macro prefix and example pool change.

Naming

Kind	Style	Examples
Variables, free functions, methods	snake_case	n_sigma, quadrature_sum, barlow_parameter, rng
Private members	snake_case_	params_, formula_
Classes, structs, type aliases	PascalCase	(none yet — add as the surface grows)
Enum values (incl. legacy plain enums)	PascalCase
Project macros	MIST_HEP_ + ALL_CAPS	MIST_HEP_BUILD_TESTS
Namespaces	lowercase	mist::hep, mist::hep::stats, mist::hep::fit
Filenames (incl. macro entry-points)	snake_case	stats.h, functions.cxx, globals.h

Local-vs-type collision rule

When a local variable would otherwise be spelled identically to its type (TF1 tf1, TH1F th1f), break the collision with one of:

1. **current_ prefix** when the variable is simply "the one being processed right now": TF1 current_fit;, TH1F current_spectrum;.
2. A semantic role name when the context warrants more specificity: TF1 levy_tsallis_fit, TH1F reference_spectrum, TH1F numerator.

Prefer the semantic role when several instances of the same type appear in the same scope; reach for current_ when no better name is available.

Output: never <tt>std::cout</tt> / <tt>std::cerr</tt> / <tt>printf</tt>

All textual output goes through mist::logger. mist-hep links mist::mist publicly, so the logger is always available.

// no
std::cout << "fitted " << n << " spectra\n";
std::cerr << "bad chi2 at point " << i << "\n";
std::printf("done\n");
 
// yes
mist::logger::info("fitted {} spectra", n);
mist::logger::warning("bad chi2 at point {}", i);
mist::logger::done("done");

ROOT-specific exception. ROOT's minimiser, RooFit, and many TF1/TH1 methods print to std::cout directly. Wrap those calls in mist::logger::ScopedCoutToMist so their output is routed through the logger's anchor protocol instead of corrupting in-flight progress bars:

{
    mist::logger::ScopedCoutToMist redirect;
    spectrum->Fit(levy_tsallis_fit.get(), "RMQ");   // ROOT chatter -> logger
}

Tests may use std::cout / std::cerr / std::printf for terse assertion macros where pulling in the logger would obscure the test itself (see test/tester_stats.cxx). Keep this minimal and prefer the logger where it reads cleanly.

File layout

Public headers live under include/mist/hep/<module>/; implementation TUs under src/hep/<module>/. The directory under include/mist/hep/ is the namespace under mist::hep:: — include/mist/hep/fit/functions.h declares symbols in mist::hep::fit. Don't break this mapping.

Note that headers go under include/mist/hep/ (not include/mist-hep/) so consumers see one mist/ include root regardless of which sibling library a header came from.

Include order

Inside each TU, group includes top-to-bottom and separate groups with a blank line:

1. The header this TU implements (for .cxx files only)
2. C / C++ standard library
3. ROOT headers
4. Other mist::* modules
5. Project-internal headers from the same module