本文整理汇总了C++中TokenStream::putback方法的典型用法代码示例。如果您正苦于以下问题：C++ TokenStream::putback方法的具体用法？C++ TokenStream::putback怎么用？C++ TokenStream::putback使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类TokenStream的用法示例。
在下文中一共展示了TokenStream::putback方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: Parse_MacroRules
/// Parse an entire macro_rules! block into a format that exec.cpp can use
MacroRulesPtr Parse_MacroRules(TokenStream& lex)
{
TRACE_FUNCTION_F("");
Token tok;
// Parse the patterns and replacements
::std::vector<MacroRule> rules;
while( GET_TOK(tok, lex) != TOK_EOF )
{
lex.putback(tok);
rules.push_back( Parse_MacroRules_Var(lex) );
if(GET_TOK(tok, lex) != TOK_SEMICOLON) {
CHECK_TOK(tok, TOK_EOF);
break;
}
}
DEBUG("- " << rules.size() << " rules");
::std::vector<MacroRulesArm> rule_arms;
// Re-parse the patterns into a unified form
for(auto& rule : rules)
{
MacroRulesArm arm = MacroRulesArm( mv$(rule.m_pattern), mv$(rule.m_contents) );
enumerate_names(arm.m_pattern, arm.m_param_names);
rule_arms.push_back( mv$(arm) );
}
auto rv = new MacroRules( );
rv->m_hygiene = lex.getHygiene();
rv->m_rules = mv$(rule_arms);
return MacroRulesPtr(rv);
}示例2: Parse_Type_Int
TypeRef Parse_Type_Int(TokenStream& lex, bool allow_trait_list)
{
//TRACE_FUNCTION;
auto ps = lex.start_span();
Token tok;
switch( GET_TOK(tok, lex) )
{
case TOK_INTERPOLATED_TYPE:
return mv$(tok.frag_type());
// '!' - Only ever used as part of function prototypes, but is kinda a type... not allowed here though
case TOK_EXCLAM:
return TypeRef( Span(tok.get_pos()), TypeData::make_Bang({}) );
// '_' = Wildcard (type inferrence variable)
case TOK_UNDERSCORE:
return TypeRef(Span(tok.get_pos()));
// 'unsafe' - An unsafe function type
case TOK_RWORD_UNSAFE:
// 'extern' - A function type with an ABI
case TOK_RWORD_EXTERN:
// 'fn' - Rust function
case TOK_RWORD_FN:
PUTBACK(tok, lex);
return Parse_Type_Fn(lex);
case TOK_RWORD_IMPL:
return Parse_Type_ErasedType(lex, allow_trait_list);
// '<' - An associated type cast
case TOK_LT:
case TOK_DOUBLE_LT: {
PUTBACK(tok, lex);
auto path = Parse_Path(lex, PATH_GENERIC_TYPE);
return TypeRef(TypeRef::TagPath(), lex.end_span(mv$(ps)), mv$(path));
}
//
case TOK_RWORD_FOR: {
auto hrls = Parse_HRB(lex);
switch(LOOK_AHEAD(lex))
{
case TOK_RWORD_UNSAFE:
case TOK_RWORD_EXTERN:
case TOK_RWORD_FN:
return Parse_Type_Fn(lex, hrls);
default:
return Parse_Type_Path(lex, hrls, true);
}
}
// <ident> - Either a primitive, or a path
case TOK_IDENT:
if( lex.lookahead(0) == TOK_EXCLAM )
{
lex.getToken();
// TODO: path macros
return TypeRef(TypeRef::TagMacro(), Parse_MacroInvocation(ps, mv$(tok.str()), lex));
}
// or a primitive
//if( auto ct = coretype_fromstring(tok.str()) )
//{
// return TypeRef(TypeRef::TagPrimitive(), Span(tok.get_pos()), ct);
//}
PUTBACK(tok, lex);
return Parse_Type_Path(lex, {}, allow_trait_list);
// - Fall through to path handling
// '::' - Absolute path
case TOK_DOUBLE_COLON:
// 'self' - This relative path
case TOK_RWORD_SELF:
// 'super' - Parent relative path
case TOK_RWORD_SUPER:
// ':path' fragment
case TOK_INTERPOLATED_PATH:
PUTBACK(tok, lex);
return Parse_Type_Path(lex, {}, allow_trait_list);
// HACK! Convert && into & &
case TOK_DOUBLE_AMP:
lex.putback(Token(TOK_AMP));
// '&' - Reference type
case TOK_AMP: {
AST::LifetimeRef lifetime;
// Reference
tok = lex.getToken();
if( tok.type() == TOK_LIFETIME ) {
lifetime = AST::LifetimeRef(/*lex.point_span(), */lex.get_ident(::std::move(tok)));
tok = lex.getToken();
}
bool is_mut = false;
if( tok.type() == TOK_RWORD_MUT ) {
is_mut = true;
}
else {
PUTBACK(tok, lex);
}
return TypeRef(TypeRef::TagReference(), lex.end_span(mv$(ps)), ::std::move(lifetime), is_mut, Parse_Type(lex, false));
}
// '*' - Raw pointer
case TOK_STAR:
//.........这里部分代码省略.........