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PlaceholderParser: Simplified the parser after introducing

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the writable variables.
This commit is contained in:
Vojtech Bubnik 2023-03-20 10:25:52 +01:00
parent b9d8fe7118
commit d152b67ce5
1 changed files with 187 additions and 208 deletions
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395
src/libslic3r/PlaceholderParser.cpp
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@ -173,7 +173,11 @@ namespace client
OptWithPos(ConfigOptionConstPtr opt, boost::iterator_range<Iterator> it_range) : opt(opt), it_range(it_range) {}
ConfigOptionConstPtr opt { nullptr };
bool writable { false };
// -1 means it is a scalar variable, or it is a vector variable and index was not assigned yet or the whole vector is considered.
int index { -1 };
boost::iterator_range<Iterator> it_range;
bool has_index() const { return index != -1; }
};
template<typename ITERATOR>
@ -802,128 +806,127 @@ namespace client
}
template <typename Iterator>
static void scalar_variable_reference(
static void store_variable_index(
const MyContext *ctx,
OptWithPos<Iterator> &opt,
expr<Iterator> &output)
OptWithPos<Iterator> &opt,
int index,
Iterator it_end,
OptWithPos<Iterator> &output)
{
if (opt.opt->is_vector())
ctx->throw_exception("Referencing a vector variable when scalar is expected", opt.it_range);
switch (opt.opt->type()) {
case coFloat: output.set_d(opt.opt->getFloat()); break;
case coInt: output.set_i(opt.opt->getInt()); break;
case coString: output.set_s(static_cast<const ConfigOptionString*>(opt.opt)->value); break;
case coPercent: output.set_d(opt.opt->getFloat()); break;
case coEnum:
case coPoint: output.set_s(opt.opt->serialize()); break;
case coBool: output.set_b(opt.opt->getBool()); break;
case coFloatOrPercent:
{
std::string opt_key(opt.it_range.begin(), opt.it_range.end());
if (boost::ends_with(opt_key, "extrusion_width")) {
// Extrusion width supports defaults and a complex graph of dependencies.
output.set_d(Flow::extrusion_width(opt_key, *ctx, static_cast<unsigned int>(ctx->current_extruder_id)));
} else if (! static_cast<const ConfigOptionFloatOrPercent*>(opt.opt)->percent) {
// Not a percent, just return the value.
output.set_d(opt.opt->getFloat());
} else {
// Resolve dependencies using the "ratio_over" link to a parent value.
const ConfigOptionDef *opt_def = print_config_def.get(opt_key);
assert(opt_def != nullptr);
double v = opt.opt->getFloat() * 0.01; // percent to ratio
for (;;) {
const ConfigOption *opt_parent = opt_def->ratio_over.empty() ? nullptr : ctx->resolve_symbol(opt_def->ratio_over);
if (opt_parent == nullptr)
ctx->throw_exception("FloatOrPercent variable failed to resolve the \"ratio_over\" dependencies", opt.it_range);
if (boost::ends_with(opt_def->ratio_over, "extrusion_width")) {
// Extrusion width supports defaults and a complex graph of dependencies.
assert(opt_parent->type() == coFloatOrPercent);
v *= Flow::extrusion_width(opt_def->ratio_over, static_cast<const ConfigOptionFloatOrPercent*>(opt_parent), *ctx, static_cast<unsigned int>(ctx->current_extruder_id));
break;
}
if (opt_parent->type() == coFloat || opt_parent->type() == coFloatOrPercent) {
v *= opt_parent->getFloat();
if (opt_parent->type() == coFloat || ! static_cast<const ConfigOptionFloatOrPercent*>(opt_parent)->percent)
break;
v *= 0.01; // percent to ratio
}
// Continue one level up in the "ratio_over" hierarchy.
opt_def = print_config_def.get(opt_def->ratio_over);
assert(opt_def != nullptr);
}
output.set_d(v);
}
break;
}
default:
ctx->throw_exception("Unknown scalar variable type", opt.it_range);
}
output.it_range = opt.it_range;
if (! opt.opt->is_vector())
ctx->throw_exception("Cannot index a scalar variable", opt.it_range);
if (index < 0)
ctx->throw_exception("Referencing a vector variable with a negative index", opt.it_range);
output = opt;
output.index = index;
output.it_range.end() = it_end;
}
template <typename Iterator>
static void vector_variable_reference(
static void variable_value(
const MyContext *ctx,
OptWithPos<Iterator> &opt,
int &index,
Iterator it_end,
expr<Iterator> &output)
{
if (opt.opt->is_scalar())
ctx->throw_exception("Referencing a scalar variable when vector is expected", opt.it_range);
const ConfigOptionVectorBase *vec = static_cast<const ConfigOptionVectorBase*>(opt.opt);
if (vec->empty())
ctx->throw_exception("Indexing an empty vector variable", opt.it_range);
size_t idx = (index < 0) ? 0 : (index >= int(vec->size())) ? 0 : size_t(index);
switch (opt.opt->type()) {
case coFloats: output.set_d(static_cast<const ConfigOptionFloats *>(opt.opt)->values[idx]); break;
case coInts: output.set_i(static_cast<const ConfigOptionInts *>(opt.opt)->values[idx]); break;
case coStrings: output.set_s(static_cast<const ConfigOptionStrings *>(opt.opt)->values[idx]); break;
case coPercents: output.set_d(static_cast<const ConfigOptionPercents*>(opt.opt)->values[idx]); break;
case coPoints: output.set_s(to_string(static_cast<const ConfigOptionPoints *>(opt.opt)->values[idx])); break;
case coBools: output.set_b(static_cast<const ConfigOptionBools *>(opt.opt)->values[idx] != 0); break;
//case coEnums: output.set_s(opt.opt->vserialize()[idx]); break;
default:
ctx->throw_exception("Unknown vector variable type", opt.it_range);
if (opt.opt->is_vector()) {
if (! opt.has_index())
ctx->throw_exception("Referencing a vector variable when scalar is expected", opt.it_range);
const ConfigOptionVectorBase *vec = static_cast<const ConfigOptionVectorBase*>(opt.opt);
if (vec->empty())
ctx->throw_exception("Indexing an empty vector variable", opt.it_range);
size_t idx = (opt.index < 0) ? 0 : (opt.index >= int(vec->size())) ? 0 : size_t(opt.index);
switch (opt.opt->type()) {
case coFloats: output.set_d(static_cast<const ConfigOptionFloats *>(opt.opt)->values[idx]); break;
case coInts: output.set_i(static_cast<const ConfigOptionInts *>(opt.opt)->values[idx]); break;
case coStrings: output.set_s(static_cast<const ConfigOptionStrings *>(opt.opt)->values[idx]); break;
case coPercents: output.set_d(static_cast<const ConfigOptionPercents*>(opt.opt)->values[idx]); break;
case coPoints: output.set_s(to_string(static_cast<const ConfigOptionPoints *>(opt.opt)->values[idx])); break;
case coBools: output.set_b(static_cast<const ConfigOptionBools *>(opt.opt)->values[idx] != 0); break;
//case coEnums: output.set_s(opt.opt->vserialize()[idx]); break;
default:
ctx->throw_exception("Unknown vector variable type", opt.it_range);
}
} else {
assert(opt.opt->is_scalar());
switch (opt.opt->type()) {
case coFloat: output.set_d(opt.opt->getFloat()); break;
case coInt: output.set_i(opt.opt->getInt()); break;
case coString: output.set_s(static_cast<const ConfigOptionString*>(opt.opt)->value); break;
case coPercent: output.set_d(opt.opt->getFloat()); break;
case coEnum:
case coPoint: output.set_s(opt.opt->serialize()); break;
case coBool: output.set_b(opt.opt->getBool()); break;
case coFloatOrPercent:
{
std::string opt_key(opt.it_range.begin(), opt.it_range.end());
if (boost::ends_with(opt_key, "extrusion_width")) {
// Extrusion width supports defaults and a complex graph of dependencies.
output.set_d(Flow::extrusion_width(opt_key, *ctx, static_cast<unsigned int>(ctx->current_extruder_id)));
} else if (! static_cast<const ConfigOptionFloatOrPercent*>(opt.opt)->percent) {
// Not a percent, just return the value.
output.set_d(opt.opt->getFloat());
} else {
// Resolve dependencies using the "ratio_over" link to a parent value.
const ConfigOptionDef *opt_def = print_config_def.get(opt_key);
assert(opt_def != nullptr);
double v = opt.opt->getFloat() * 0.01; // percent to ratio
for (;;) {
const ConfigOption *opt_parent = opt_def->ratio_over.empty() ? nullptr : ctx->resolve_symbol(opt_def->ratio_over);
if (opt_parent == nullptr)
ctx->throw_exception("FloatOrPercent variable failed to resolve the \"ratio_over\" dependencies", opt.it_range);
if (boost::ends_with(opt_def->ratio_over, "extrusion_width")) {
// Extrusion width supports defaults and a complex graph of dependencies.
assert(opt_parent->type() == coFloatOrPercent);
v *= Flow::extrusion_width(opt_def->ratio_over, static_cast<const ConfigOptionFloatOrPercent*>(opt_parent), *ctx, static_cast<unsigned int>(ctx->current_extruder_id));
break;
}
if (opt_parent->type() == coFloat || opt_parent->type() == coFloatOrPercent) {
v *= opt_parent->getFloat();
if (opt_parent->type() == coFloat || ! static_cast<const ConfigOptionFloatOrPercent*>(opt_parent)->percent)
break;
v *= 0.01; // percent to ratio
}
// Continue one level up in the "ratio_over" hierarchy.
opt_def = print_config_def.get(opt_def->ratio_over);
assert(opt_def != nullptr);
}
output.set_d(v);
}
break;
}
default:
ctx->throw_exception("Unknown scalar variable type", opt.it_range);
}
}
output.it_range = boost::iterator_range<Iterator>(opt.it_range.begin(), it_end);
output.it_range = opt.it_range;
}
// Return a boolean value, true if the scalar variable referenced by "opt" is nullable and it has a nil value.
template <typename Iterator>
static void is_nil_test_scalar(
const MyContext *ctx,
OptWithPos<Iterator> &opt,
expr<Iterator> &output)
{
if (opt.opt->is_vector())
ctx->throw_exception("Referencing a vector variable when scalar is expected", opt.it_range);
output.set_b(opt.opt->is_nil());
output.it_range = opt.it_range;
}
// Return a boolean value, true if an element of a vector variable referenced by "opt[index]" is nullable and it has a nil value.
template <typename Iterator>
static void is_nil_test_vector(
static void is_nil_test(
const MyContext *ctx,
OptWithPos<Iterator> &opt,
int &index,
Iterator it_end,
expr<Iterator> &output)
{
if (opt.opt->is_scalar())
ctx->throw_exception("Referencing a scalar variable when vector is expected", opt.it_range);
const ConfigOptionVectorBase *vec = static_cast<const ConfigOptionVectorBase*>(opt.opt);
if (vec->empty())
ctx->throw_exception("Indexing an empty vector variable", opt.it_range);
size_t idx = (index < 0) ? 0 : (index >= int(vec->size())) ? 0 : size_t(index);
output.set_b(static_cast<const ConfigOptionVectorBase*>(opt.opt)->is_nil(idx));
output.it_range = boost::iterator_range<Iterator>(opt.it_range.begin(), it_end);
if (opt.opt->is_vector()) {
if (! opt.has_index())
ctx->throw_exception("Referencing a vector variable when scalar is expected", opt.it_range);
const ConfigOptionVectorBase *vec = static_cast<const ConfigOptionVectorBase*>(opt.opt);
if (vec->empty())
ctx->throw_exception("Indexing an empty vector variable", opt.it_range);
output.set_b(static_cast<const ConfigOptionVectorBase*>(opt.opt)->is_nil(opt.index >= int(vec->size()) ? 0 : size_t(opt.index)));
} else {
assert(opt.opt->is_scalar());
output.set_b(opt.opt->is_nil());
}
output.it_range = opt.it_range;
}
// Decoding a scalar variable symbol "opt", assigning it a value of "param".
template <typename Iterator>
static void scalar_variable_assign(
static void variable_assign(
const MyContext *ctx,
OptWithPos<Iterator> &opt,
expr<Iterator> &param,
@ -932,83 +935,71 @@ namespace client
{
if (! opt.writable)
ctx->throw_exception("Cannot modify a read-only variable", opt.it_range);
if (opt.opt->is_vector())
ctx->throw_exception("Referencing an output vector variable when scalar is expected", opt.it_range);
ConfigOption *wropt = const_cast<ConfigOption*>(opt.opt);
switch (wropt->type()) {
case coFloat:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionFloat*>(wropt)->value = param.as_d();
break;
case coInt:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionInt*>(wropt)->value = param.as_i();
break;
case coString:
static_cast<ConfigOptionString*>(wropt)->value = param.to_string();
break;
case coPercent:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionPercent*>(wropt)->value = param.as_d();
break;
case coBool:
if (param.type() != expr<Iterator>::TYPE_BOOL)
ctx->throw_exception("Right side is not a boolean expression", param.it_range);
static_cast<ConfigOptionBool*>(wropt)->value = param.b();
break;
default:
ctx->throw_exception("Unsupported output scalar variable type", opt.it_range);
}
out.clear();
}
template <typename Iterator>
static void vector_variable_assign(
const MyContext *ctx,
OptWithPos<Iterator> &opt,
int &index,
expr<Iterator> &param,
// Not used, just clear it.
std::string &out)
{
if (! opt.writable)
ctx->throw_exception("Cannot modify a read-only variable", opt.it_range);
if (opt.opt->is_scalar())
ctx->throw_exception("Referencing an output scalar variable when vector is expected", opt.it_range);
ConfigOptionVectorBase *vec = const_cast<ConfigOptionVectorBase*>(static_cast<const ConfigOptionVectorBase*>(opt.opt));
if (vec->empty())
ctx->throw_exception("Indexing an empty vector variable", opt.it_range);
if (index < 0 || index >= int(vec->size()))
ctx->throw_exception("Index out of range", opt.it_range);
switch (opt.opt->type()) {
case coFloats:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionFloats*>(vec)->values[index] = param.as_d();
break;
case coInts:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionInts*>(vec)->values[index] = param.as_i();
break;
case coStrings:
static_cast<ConfigOptionStrings*>(vec)->values[index] = param.to_string();
break;
case coPercents:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionPercents*>(vec)->values[index] = param.as_d();
break;
case coBools:
if (param.type() != expr<Iterator>::TYPE_BOOL)
ctx->throw_exception("Right side is not a boolean expression", param.it_range);
static_cast<ConfigOptionBools*>(vec)->values[index] = param.b();
break;
default:
ctx->throw_exception("Unsupported output vector variable type", opt.it_range);
if (opt.opt->is_vector()) {
if (! opt.has_index())
ctx->throw_exception("Referencing an output vector variable when scalar is expected", opt.it_range);
ConfigOptionVectorBase *vec = const_cast<ConfigOptionVectorBase*>(static_cast<const ConfigOptionVectorBase*>(opt.opt));
if (vec->empty())
ctx->throw_exception("Indexing an empty vector variable", opt.it_range);
if (opt.index >= int(vec->size()))
ctx->throw_exception("Index out of range", opt.it_range);
switch (opt.opt->type()) {
case coFloats:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionFloats*>(vec)->values[opt.index] = param.as_d();
break;
case coInts:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionInts*>(vec)->values[opt.index] = param.as_i();
break;
case coStrings:
static_cast<ConfigOptionStrings*>(vec)->values[opt.index] = param.to_string();
break;
case coPercents:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionPercents*>(vec)->values[opt.index] = param.as_d();
break;
case coBools:
if (param.type() != expr<Iterator>::TYPE_BOOL)
ctx->throw_exception("Right side is not a boolean expression", param.it_range);
static_cast<ConfigOptionBools*>(vec)->values[opt.index] = param.b();
break;
default:
ctx->throw_exception("Unsupported output vector variable type", opt.it_range);
}
} else {
assert(opt.opt->is_scalar());
ConfigOption *wropt = const_cast<ConfigOption*>(opt.opt);
switch (wropt->type()) {
case coFloat:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionFloat*>(wropt)->value = param.as_d();
break;
case coInt:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionInt*>(wropt)->value = param.as_i();
break;
case coString:
static_cast<ConfigOptionString*>(wropt)->value = param.to_string();
break;
case coPercent:
if (param.type() != expr<Iterator>::TYPE_INT && param.type() != expr<Iterator>::TYPE_DOUBLE)
ctx->throw_exception("Right side is not a numeric expression", param.it_range);
static_cast<ConfigOptionPercent*>(wropt)->value = param.as_d();
break;
case coBool:
if (param.type() != expr<Iterator>::TYPE_BOOL)
ctx->throw_exception("Right side is not a boolean expression", param.it_range);
static_cast<ConfigOptionBool*>(wropt)->value = param.b();
break;
default:
ctx->throw_exception("Unsupported output scalar variable type", opt.it_range);
}
}
out.clear();
}
@ -1110,9 +1101,9 @@ namespace client
{ "multiplicative_expression", "Expecting an expression." },
{ "unary_expression", "Expecting an expression." },
{ "optional_parameter", "Expecting a closing brace or an optional parameter." },
{ "scalar_variable_reference", "Expecting a scalar variable reference."},
{ "is_nil_test", "Expecting a scalar variable reference."},
{ "variable_reference", "Expecting a variable reference."},
{ "is_nil_test", "Expecting a scalar variable reference."},
{ "variable", "Expecting a variable name."},
{ "regular_expression", "Expecting a regular expression."}
};
@ -1359,13 +1350,8 @@ namespace client
multiplicative_expression.name("multiplicative_expression");
assignment_statement =
variable_reference(_r1)[_a = _1] >>
(
('[' >> additive_expression(_r1)[px::bind(&MyContext::evaluate_index<Iterator>, _1, _b)] >> ']' >> '=' >> additive_expression(_r1))
[px::bind(&MyContext::vector_variable_assign<Iterator>, _r1, _a, _b, _2, _val)]
| ('=' >> additive_expression(_r1))
[px::bind(&MyContext::scalar_variable_assign<Iterator>, _r1, _a, _1, _val)]
);
(variable_reference(_r1) >> '=' > additive_expression(_r1))
[px::bind(&MyContext::variable_assign<Iterator>, _r1, _1, _2, _val)];
struct FactorActions {
static void set_start_pos(Iterator &start_pos, expr<Iterator> &out)
@ -1392,7 +1378,7 @@ namespace client
static void noexpr(expr<Iterator> &out) { out.reset(); }
};
unary_expression = iter_pos[px::bind(&FactorActions::set_start_pos, _1, _val)] >> (
scalar_variable_reference(_r1) [ _val = _1 ]
variable_reference(_r1) [px::bind(&MyContext::variable_value<Iterator>, _r1, _1, _val)]
| (lit('(') > conditional_expression(_r1) > ')' > iter_pos) [ px::bind(&FactorActions::expr_, _1, _2, _val) ]
| (lit('-') > unary_expression(_r1) ) [ px::bind(&FactorActions::minus_, _1, _val) ]
| (lit('+') > unary_expression(_r1) > iter_pos) [ px::bind(&FactorActions::expr_, _1, _2, _val) ]
@ -1424,27 +1410,20 @@ namespace client
);
optional_parameter.name("optional_parameter");
scalar_variable_reference =
variable_reference(_r1)[_a=_1] >>
(
('[' > additive_expression(_r1)[px::bind(&MyContext::evaluate_index<Iterator>, _1, _b)] > ']' >
iter_pos[px::bind(&MyContext::vector_variable_reference<Iterator>, _r1, _a, _b, _1, _val)])
| eps[px::bind(&MyContext::scalar_variable_reference<Iterator>, _r1, _a, _val)]
);
scalar_variable_reference.name("scalar variable reference");
is_nil_test = variable_reference(_r1)[px::bind(&MyContext::is_nil_test<Iterator>, _r1, _1, _val)];
is_nil_test.name("is_nil test");
variable_reference = identifier
[ px::bind(&MyContext::resolve_variable<Iterator>, _r1, _1, _val) ];
variable_reference =
variable(_r1)[_a=_1] >>
(
('[' > additive_expression(_r1)[px::bind(&MyContext::evaluate_index<Iterator>, _1, _b)] > ']' > iter_pos)
[px::bind(&MyContext::store_variable_index<Iterator>, _r1, _a, _b, _2, _val)]
| eps[_val=_a]
);
variable_reference.name("variable reference");
is_nil_test =
variable_reference(_r1)[_a=_1] >>
(
('[' > additive_expression(_r1)[px::bind(&MyContext::evaluate_index<Iterator>, _1, _b)] > ']' >
iter_pos[px::bind(&MyContext::is_nil_test_vector<Iterator>, _r1, _a, _b, _1, _val)])
| eps[px::bind(&MyContext::is_nil_test_scalar<Iterator>, _r1, _a, _val)]
);
is_nil_test.name("is_nil test");
variable = identifier[ px::bind(&MyContext::resolve_variable<Iterator>, _r1, _1, _val) ];
variable.name("variable reference");
regular_expression = raw[lexeme['/' > *((utf8char - char_('\\') - char_('/')) | ('\\' > char_)) > '/']];
regular_expression.name("regular_expression");
@ -1488,8 +1467,8 @@ namespace client
debug(multiplicative_expression);
debug(unary_expression);
debug(optional_parameter);
debug(scalar_variable_reference);
debug(variable_reference);
debug(variable);
debug(is_nil_test);
debug(regular_expression);
}
@ -1533,11 +1512,11 @@ namespace client
// Evaluate boolean expression into bool.
qi::rule<Iterator, bool(const MyContext*), spirit_encoding::space_type> bool_expr_eval;
// Reference of a scalar variable, or reference to a field of a vector variable.
qi::rule<Iterator, expr<Iterator>(const MyContext*), qi::locals<OptWithPos<Iterator>, int>, spirit_encoding::space_type> scalar_variable_reference;
qi::rule<Iterator, OptWithPos<Iterator>(const MyContext*), qi::locals<OptWithPos<Iterator>, int>, spirit_encoding::space_type> variable_reference;
// Rule to translate an identifier to a ConfigOption, or to fail.
qi::rule<Iterator, OptWithPos<Iterator>(const MyContext*), spirit_encoding::space_type> variable_reference;
qi::rule<Iterator, OptWithPos<Iterator>(const MyContext*), spirit_encoding::space_type> variable;
// Evaluating whether a nullable variable is nil.
qi::rule<Iterator, expr<Iterator>(const MyContext*), qi::locals<OptWithPos<Iterator>, int>, spirit_encoding::space_type> is_nil_test;
qi::rule<Iterator, expr<Iterator>(const MyContext*), spirit_encoding::space_type> is_nil_test;
qi::rule<Iterator, std::string(const MyContext*), qi::locals<bool, bool>, spirit_encoding::space_type> if_else_output;
qi::rule<Iterator, std::string(const MyContext*), qi::locals<OptWithPos<Iterator>, int>, spirit_encoding::space_type> assignment_statement;