diff options
| -rw-r--r-- | ast.cpp | 64 |
1 files changed, 61 insertions, 3 deletions
@@ -113,12 +113,40 @@ public: nextat++; } return true; + } else if(source[index]=='"'){ + for(nextat=index+1;nextat<size;nextat++){ + if(source[nextat]=='\\'){ + nextat++; + if(nextat==size){ + throw ParseError("Unexpected end of file after '\\' in string"); + } + } else if(source[nextat]=='"'){ + break; + } + } + if(nextat==size){ + throw ParseError("Unexpected end of file in string"); + } + nextat++; + return true; } else { throw ParseError(string("Invalid token starting with '")+source[index]+"'"); } } }; +static char parseHex(char c){ + if(c>='0'&&c<='9'){ + return c-'0'; + } else if(c>='a'&&c<='f'){ + return c-'a'+10; + } else if(c>='A'&&c<='F'){ + return c-'A'+10; + } else { + return -1; + } +} + AST& AST::parse(AST::Tokeniser &tokeniser){ if(tokeniser.eof()){ throw ParseError("No tokens to parse"); @@ -128,15 +156,12 @@ AST& AST::parse(AST::Tokeniser &tokeniser){ throw logic_error("Unexpected empty token from tokeniser"); } if(isdigit(token[0])||(token.size()>1&&token[0]=='-'&&isdigit(token[1]))){ - // cerr<<"AST::parse: type = number"<<endl; type=Type::number; numval=strtol(token.data(),NULL,10); } else if(iswordchar(token[0])){ - // cerr<<"AST::parse: type = name"<<endl; type=Type::name; nameval=token; } else if(token=="("){ - // cerr<<"AST::parse: type = tuple"<<endl; type=Type::tuple; while(true){ if(!tokeniser.advance()){ @@ -165,6 +190,39 @@ AST& AST::parse(AST::Tokeniser &tokeniser){ throw ParseError("Body expected after argument of '\\'"); } lambdaval.body=AST().parse(tokeniser); + } else if(token[0]=='"'){ + if(token.back()!='"'){ + throw logic_error("No string terminator at end of string token from tokeniser"); + } + type=Type::string; + for(i64 i=1;i<(i64)token.size()-1;i++){ + if(token[i]=='\\'){ + switch(token[i+1]){ + case 't': strval+='\t'; break; + case 'n': strval+='\n'; break; + case 'r': strval+='\r'; break; + case 'x':{ + if(i+3>=(i64)token.size()-1){ + throw ParseError("Not enough characters after hexadecimal" + " escape sequence"); + } + char hex1=parseHex(token[i+2]), + hex2=parseHex(token[i+3]); + if(hex1==-1||hex2==-1){ + throw ParseError("Invalid characters in hexadecimal" + " escape sequence"); + } + strval+=(hex1<<4)|hex2; + i+=2; + break; + } + default: strval+=token[i+1]; break; + } + i++; + } else { + strval+=token[i]; + } + } } else if(token==")"){ throw ParseError("Unexpected token '"+token+"'"); } else { |