%glr-parser %pure-parser %locations %error-verbose %parse-param { yyscan_t scanner } %parse-param { void * data } %lex-param { yyscan_t scanner } %{ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <aterm2.h> #include "parser-tab.h" #include "lexer-tab.h" typedef ATerm Expr; typedef ATerm ValidValues; typedef ATerm DefaultValue; typedef ATerm Pos; #include "nixexpr-ast.hh" void setParseResult(void * data, ATerm t); void parseError(void * data, char * error, int line, int column); ATerm absParsedPath(void * data, ATerm t); ATerm fixAttrs(int recursive, ATermList as); const char * getPath(void * data); void backToString(yyscan_t scanner); void yyerror(YYLTYPE * loc, yyscan_t scanner, void * data, char * s) { parseError(data, s, loc->first_line, loc->first_column); } ATerm toATerm(const char * s) { return (ATerm) ATmakeAppl0(ATmakeAFun((char *) s, 0, ATtrue)); } static Pos makeCurPos(YYLTYPE * loc, void * data) { return makePos(toATerm(getPath(data)), loc->first_line, loc->first_column); } #define CUR_POS makeCurPos(yylocp, data) /* Make sure that the parse stack is scanned by the ATerm garbage collector. */ static void * mallocAndProtect(size_t size) { void * p = malloc(size); if (p) ATprotectMemory(p, size); return p; } static void freeAndUnprotect(void * p) { ATunprotectMemory(p); free(p); } #define YYMALLOC mallocAndProtect #define YYFREE freeAndUnprotect %} %union { ATerm t; ATermList ts; } %type <t> start expr expr_function expr_if expr_op %type <t> expr_app expr_select expr_simple bind inheritsrc formal %type <ts> binds ids expr_list formals string_parts %token <t> ID INT STR PATH URI %token IF THEN ELSE ASSERT WITH LET REC INHERIT EQ NEQ AND OR IMPL %token DOLLAR_CURLY /* == ${ */ %nonassoc IMPL %left OR %left AND %nonassoc EQ NEQ %right UPDATE %left NEG %left '+' %right CONCAT %nonassoc '?' %nonassoc '~' %% start: expr { setParseResult(data, $1); }; expr: expr_function; expr_function : '{' formals '}' ':' expr_function { $$ = makeFunction($2, $5, CUR_POS); } | ID ':' expr_function { $$ = makeFunction1($1, $3, CUR_POS); } | ASSERT expr ';' expr_function { $$ = makeAssert($2, $4, CUR_POS); } | WITH expr ';' expr_function { $$ = makeWith($2, $4, CUR_POS); } | expr_if ; expr_if : IF expr THEN expr ELSE expr { $$ = makeIf($2, $4, $6); } | expr_op ; expr_op : '!' expr_op %prec NEG { $$ = makeOpNot($2); } | expr_op EQ expr_op { $$ = makeOpEq($1, $3); } | expr_op NEQ expr_op { $$ = makeOpNEq($1, $3); } | expr_op AND expr_op { $$ = makeOpAnd($1, $3); } | expr_op OR expr_op { $$ = makeOpOr($1, $3); } | expr_op IMPL expr_op { $$ = makeOpImpl($1, $3); } | expr_op UPDATE expr_op { $$ = makeOpUpdate($1, $3); } | expr_op '~' expr_op { $$ = makeSubPath($1, $3); } | expr_op '?' ID { $$ = makeOpHasAttr($1, $3); } | expr_op '+' expr_op { $$ = makeOpPlus($1, $3); } | expr_op CONCAT expr_op { $$ = makeOpConcat($1, $3); } | expr_app ; expr_app : expr_app expr_select { $$ = makeCall($1, $2); } | expr_select { $$ = $1; } ; expr_select : expr_select '.' ID { $$ = makeSelect($1, $3); } | expr_simple { $$ = $1; } ; expr_simple : ID { $$ = makeVar($1); } | INT { $$ = makeInt(ATgetInt((ATermInt) $1)); } | '"' string_parts '"' { /* For efficiency, and to simplify parse trees a bit. */ if ($2 == ATempty) $$ = makeStr(toATerm("")); else if (ATgetNext($2) == ATempty) $$ = ATgetFirst($2); else $$ = makeConcatStrings(ATreverse($2)); } | PATH { $$ = makePath(absParsedPath(data, $1)); } | URI { $$ = makeUri($1); } | '(' expr ')' { $$ = $2; } /* Let expressions `let {..., body = ...}' are just desugared into `(rec {..., body = ...}).body'. */ | LET '{' binds '}' { $$ = makeSelect(fixAttrs(1, $3), toATerm("body")); } | REC '{' binds '}' { $$ = fixAttrs(1, $3); } | '{' binds '}' { $$ = fixAttrs(0, $2); } | '[' expr_list ']' { $$ = makeList($2); } ; string_parts : string_parts STR { $$ = ATinsert($1, $2); } | string_parts DOLLAR_CURLY expr '}' { backToString(scanner); $$ = ATinsert($1, $3); } | { $$ = ATempty; } ; binds : binds bind { $$ = ATinsert($1, $2); } | { $$ = ATempty; } ; bind : ID '=' expr ';' { $$ = makeBind($1, $3, CUR_POS); } | INHERIT inheritsrc ids ';' { $$ = makeInherit($2, $3, CUR_POS); } ; inheritsrc : '(' expr ')' { $$ = $2; } | { $$ = makeScope(); } ; ids: ids ID { $$ = ATinsert($1, $2); } | { $$ = ATempty; }; expr_list : expr_select expr_list { $$ = ATinsert($2, $1); } /* yes, this is right-recursive, but it doesn't matter since otherwise we would need ATreverse which requires unbounded stack space */ | { $$ = ATempty; } ; formals : formal ',' formals { $$ = ATinsert($3, $1); } /* idem - right recursive */ | formal { $$ = ATinsert(ATempty, $1); } ; formal : ID { $$ = makeFormal($1, makeUnrestrictedValues(), makeNoDefaultValue()); } // | ID ':' '[' expr_list ']' { $$ = makeDefFormal($1, $3); } | ID '?' expr { $$ = makeFormal($1, makeUnrestrictedValues(), makeDefaultValue($3)); } ; %%