cpp-peglib/language/parser.cc
2015-06-25 20:06:00 -04:00

113 lines
4.7 KiB
C++

#include "parser.hpp"
using namespace peglib;
using namespace std;
static auto g_grammar = R"(
PROGRAM <- _ STATEMENTS
STATEMENTS <- (EXPRESSION (';' _)?)*
EXPRESSION <- ASSIGNMENT / PRIMARY
ASSIGNMENT <- MUTABLE IDENTIFIER '=' _ EXPRESSION
WHILE <- 'while' _ EXPRESSION BLOCK
IF <- 'if' _ EXPRESSION BLOCK ('else' _ 'if' _ EXPRESSION BLOCK)* ('else' _ BLOCK)?
FUNCTION_CALL <- IDENTIFIER ARGUMENTS
ARGUMENTS <- '(' _ (EXPRESSION (', ' _ EXPRESSION)*)? ')' _
PRIMARY <- LOGICAL_OR ('||' _ LOGICAL_OR)*
LOGICAL_OR <- LOGICAL_AND ('&&' _ LOGICAL_AND)*
LOGICAL_AND <- CONDITION (CONDITION_OPERATOR CONDITION)*
CONDITION <- TERM (TERM_OPERATOR TERM)*
TERM <- UNARY_PLUS_OPERATOR? UNARY_PLUS
UNARY_PLUS <- UNARY_MINUS_OPERATOR? UNARY_MINUS
UNARY_MINUS <- UNARY_NOT_OPERATOR? UNARY_NOT
UNARY_NOT <- FACTOR (FACTOR_OPERATOR FACTOR)*
FACTOR <- WHILE / IF / FUNCTION / FUNCTION_CALL / ARRAY / ARRAY_REFERENCE / NUMBER / BOOLEAN / STRING / INTERPOLATED_STRING / IDENTIFIER / '(' _ EXPRESSION ')' _
FUNCTION <- 'fn' _ PARAMETERS BLOCK
PARAMETERS <- '(' _ (PARAMETER (',' _ PARAMETER)*)? ')' _
PARAMETER <- MUTABLE IDENTIFIER
ARRAY <- '[' _ (EXPRESSION (',' _ EXPRESSION)*) ']' _
ARRAY_REFERENCE <- IDENTIFIER '[' _ EXPRESSION ']' _
BLOCK <- '{' _ STATEMENTS '}' _
CONDITION_OPERATOR <- < ('==' / '!=' / '<=' / '<' / '>=' / '>') > _
TERM_OPERATOR <- < [-+] > _
UNARY_PLUS_OPERATOR <- < '+' > _
UNARY_MINUS_OPERATOR <- < '-' > _
UNARY_NOT_OPERATOR <- < '!' > _
FACTOR_OPERATOR <- < [*/%] > _
IDENTIFIER <- < [a-zA-Z_][a-zA-Z0-9_]* > _
NUMBER <- < [0-9]+ > _
BOOLEAN <- < ('true' / 'false') > _
STRING <- ['] < (!['] .)* > ['] _
INTERPOLATED_STRING <- '"' ('{' _ EXPRESSION '}' / INTERPOLATED_CONTENT)* '"' _
INTERPOLATED_CONTENT <- (!["{] .) (!["{] .)*
MUTABLE <- < 'mut'? > _
~_ <- (Space / EndOfLine / Comment)*
Space <- ' ' / '\t'
EndOfLine <- '\r\n' / '\n' / '\r'
EndOfFile <- !.
Comment <- '/*' (!'*/' .)* '*/' / ('#' / '//') (!(EndOfLine / EndOfFile) .)* (EndOfLine / EndOfFile)
)";
peg& get_parser()
{
static peg parser;
static bool initialized = false;
if (!initialized) {
initialized = true;
parser.log = [&](size_t ln, size_t col, const string& msg) {
cerr << ln << ":" << col << ": " << msg << endl;
};
if (!parser.load_grammar(g_grammar)) {
throw logic_error("invalid peg grammar");
}
parser.enable_ast(true, {
/*
Definition, Tag Optimize
---------------------- ------------------ ---------- */
{ "STATEMENTS", Statements, false },
{ "WHILE", While, false },
{ "ASSIGNMENT", Assignment, false },
{ "IF", If, false },
{ "FUNCTION", Function, false },
{ "PARAMETERS", Default, false },
{ "FUNCTION_CALL", FunctionCall, false },
{ "ARRAY", Array, false },
{ "ARRAY_REFERENCE", ArrayReference, false },
{ "ARGUMENTS", Default, false },
{ "PRIMARY", LogicalOr, true },
{ "LOGICAL_OR", LogicalAnd, true },
{ "LOGICAL_AND", Condition, true },
{ "CONDITION", BinExpresion, true },
{ "TERM", UnaryPlus, true },
{ "UNARY_PLUS", UnaryMinus, true },
{ "UNARY_MINUS", UnaryNot, true },
{ "UNARY_NOT", BinExpresion, true },
{ "NUMBER", Number, false },
{ "BOOLEAN", Boolean, false },
{ "IDENTIFIER", Identifier, false },
{ "INTERPOLATED_STRING", InterpolatedString, false },
});
}
return parser;
}
// vim: et ts=4 sw=4 cin cino={1s ff=unix