NB: the “overwrite” option only works for the same type of “learnt_in” value,
i.e. an integer-valued “learnt_in” cannot replace a date-valued “learnt_in” and
vice versa.

– Harmonize location output for warnings so that it is the same as for
  errors (i.e. more explicit about what is the line number and the column number)
– Remove obsolete stuff for delayed error messages that should have been
  removed in db1f6c29.
– Factorize some printing logic with ParsingDriver::undeclared_model_variable_error().
– Simplify WarningConsolidation class

The call to model_error() would return and lead to an incorrect dereferencing
of the optional<int> rv.

The call to model_error() should have been replaced by a call to error() in
db1f6c29. Then the move to an optional<int> in
46b2c735 introduced the bug.

See https://forum.dynare.org/t/preprocessing-failed-for-specific-mod-file/26705

– New “heterogeneity_dimension” statement
– New option “heterogeneity” to “var”, “varexo”, “parameters”, “model” and
  “shocks” statements
– New “SUM()” operator in “model” block

[skip ci]

Ref. dynare#1929

The vector of lower and upper bounds is now provided by
{static,dynamic}_complementarity_conditions.m (which accepts parameters as an
argument, in preparation for the possibility of having parameters in
complementarity conditions).

The index that denotes the reordering of equation residuals (so that the
residual of an equation appears at the index of the endogenous appearing in the
complementarity condition) is now in “M_.{static,dynamic}_mcp_equations_reordering”.

Constraints declared through the ramsey_constraints block are also incorporated
in this new interface (and therefore “M_.ramsey_model_constraints” has been
removed).

The symbol can be either input:
– as ⟂ in UTF-8 (codepoint U+27C2)
– or as _|_ in ASCII

The old syntax using the “mcp” tag is now obsolete, but kept for backward
compatibility.

By the way, also improve the terminology used in variable and method names: a
“constraint” is something like “ZLB” or “INEG”, a regime is a state in which
constraints are either binding or relaxed.

Really closes: #103

In particular, emit more explicit error messages in the presence of
inconsistencies.

Closes: #103

Closes: #124

The old name is still accepted, but will trigger a deprecation warning.

Automatically detected by clang-tidy with performance-move-const-arg check.

Do not make the modification for Tokenizer::location type, since we have no
guarantee that the type will remain trivially-copyable in the future.

Automatically detected by clang-tidy using the performance-faster-string-find
check.

Avoids an unnecessary copy.

Automatically detected using clang-tidy with modernize-use-emplace check.

NB: does not (yet) works with Occbin regime-specific equations.

Ref. dynare#1890

Incidentally, makes tag names case-insensitive in “model_replace” and
“model_remove”, which is consistent with tag declarations.

Currently defaults to 0.

This is a restoration of the behaviour that was present in 5.x.

For consistency with other such classes, since it represents the homotopy_setup
block.

Adapt the code accordingly.

Closes: #113

Those two settings were previously always at their default value for the static
model, independently of what the user would set in the .mod file.

By the way:
– improve the semantics by having a consistent treatment of empty substring
  components (previously, only the last one was ignored)
– move it to DataTree to make it more accessible from elsewhere (even though
  ideally it should be in a “utilities” namespace).