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Diffstat (limited to 'third_party/nix/src/libexpr/parser.y')
| -rw-r--r-- | third_party/nix/src/libexpr/parser.y | 359 |
1 files changed, 359 insertions, 0 deletions
diff --git a/third_party/nix/src/libexpr/parser.y b/third_party/nix/src/libexpr/parser.y new file mode 100644 index 0000000000..a8af06802f --- /dev/null +++ b/third_party/nix/src/libexpr/parser.y @@ -0,0 +1,359 @@ +%glr-parser +%locations +%define parse.error verbose +%define api.pure true +%defines +/* %no-lines */ +%parse-param { void * scanner } +%parse-param { nix::ParseData * data } +%lex-param { void * scanner } +%lex-param { nix::ParseData * data } +%expect 1 +%expect-rr 1 + +%code requires { +#define YY_NO_INPUT 1 // disable unused yyinput features +#include "libexpr/parser.hh" + +struct YYSTYPE { + union { + nix::Expr * e; + nix::ExprList * list; + nix::ExprAttrs * attrs; + nix::Formals * formals; + nix::Formal * formal; + nix::NixInt n; + nix::NixFloat nf; + const char * id; // !!! -> Symbol + char * path; + char * uri; + nix::AttrNameVector * attrNames; + nix::VectorExprs * string_parts; + }; +}; + +} + +%{ + +#include "generated/parser-tab.hh" +#include "generated/lexer-tab.hh" + +YY_DECL; + +using namespace nix; + +namespace nix { + +static inline Pos makeCurPos(const YYLTYPE& loc, ParseData* data) { + return Pos(data->path, loc.first_line, loc.first_column); +} + +void yyerror(YYLTYPE* loc, yyscan_t scanner, ParseData* data, + const char* error) { + data->error = (format("%1%, at %2%") % error % makeCurPos(*loc, data)).str(); +} + +} + +%} + +%type <e> start expr expr_function expr_if expr_op +%type <e> expr_app expr_select expr_simple +%type <list> expr_list +%type <attrs> binds +%type <formals> formals +%type <formal> formal +%type <attrNames> attrs attrpath +%type <string_parts> string_parts_interpolated ind_string_parts +%type <e> string_parts string_attr +%type <id> attr +%token <id> ID ATTRPATH +%token <e> STR IND_STR +%token <n> INT +%token <nf> FLOAT +%token <path> PATH HPATH SPATH +%token <uri> URI +%token IF THEN ELSE ASSERT WITH LET IN REC INHERIT EQ NEQ AND OR IMPL OR_KW +%token DOLLAR_CURLY /* == ${ */ +%token IND_STRING_OPEN IND_STRING_CLOSE +%token ELLIPSIS + +%right IMPL +%left OR +%left AND +%nonassoc EQ NEQ +%nonassoc '<' '>' LEQ GEQ +%right UPDATE +%left NOT +%left '+' '-' +%left '*' '/' +%right CONCAT +%nonassoc '?' +%nonassoc NEGATE + +%% + +start: expr { data->result = $1; }; + +expr: expr_function; + +expr_function + : ID ':' expr_function + { $$ = new ExprLambda(CUR_POS, data->symbols.Create($1), false, 0, $3); } + | '{' formals '}' ':' expr_function + { $$ = new ExprLambda(CUR_POS, data->symbols.Create(""), true, $2, $5); } + | '{' formals '}' '@' ID ':' expr_function + { $$ = new ExprLambda(CUR_POS, data->symbols.Create($5), true, $2, $7); } + | ID '@' '{' formals '}' ':' expr_function + { $$ = new ExprLambda(CUR_POS, data->symbols.Create($1), true, $4, $7); } + | ASSERT expr ';' expr_function + { $$ = new ExprAssert(CUR_POS, $2, $4); } + | WITH expr ';' expr_function + { $$ = new ExprWith(CUR_POS, $2, $4); } + | LET binds IN expr_function + { if (!$2->dynamicAttrs.empty()) + throw ParseError(format("dynamic attributes not allowed in let at %1%") + % CUR_POS); + $$ = new ExprLet($2, $4); + } + | expr_if + ; + +expr_if + : IF expr THEN expr ELSE expr { $$ = new ExprIf(CUR_POS, $2, $4, $6); } + | expr_op + ; + +expr_op + : '!' expr_op %prec NOT { $$ = new ExprOpNot(CUR_POS, $2); } + | '-' expr_op %prec NEGATE { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.Create("__sub")), new ExprInt(0)), $2); } + | expr_op EQ expr_op { $$ = new ExprOpEq(CUR_POS, $1, $3); } + | expr_op NEQ expr_op { $$ = new ExprOpNEq(CUR_POS, $1, $3); } + | expr_op '<' expr_op { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.Create("__lessThan")), $1), $3); } + | expr_op LEQ expr_op { $$ = new ExprOpNot(new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.Create("__lessThan")), $3), $1)); } + | expr_op '>' expr_op { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.Create("__lessThan")), $3), $1); } + | expr_op GEQ expr_op { $$ = new ExprOpNot(new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.Create("__lessThan")), $1), $3)); } + | expr_op AND expr_op { $$ = new ExprOpAnd(CUR_POS, $1, $3); } + | expr_op OR expr_op { $$ = new ExprOpOr(CUR_POS, $1, $3); } + | expr_op IMPL expr_op { $$ = new ExprOpImpl(CUR_POS, $1, $3); } + | expr_op UPDATE expr_op { $$ = new ExprOpUpdate(CUR_POS, $1, $3); } + | expr_op '?' attrpath { $$ = new ExprOpHasAttr(CUR_POS, $1, *$3); } + | expr_op '+' expr_op + { $$ = new ExprConcatStrings(CUR_POS, false, new nix::VectorExprs({$1, $3})); } + | expr_op '-' expr_op { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.Create("__sub")), $1), $3); } + | expr_op '*' expr_op { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.Create("__mul")), $1), $3); } + | expr_op '/' expr_op { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.Create("__div")), $1), $3); } + | expr_op CONCAT expr_op { $$ = new ExprOpConcatLists(CUR_POS, $1, $3); } + | expr_app + ; + +expr_app + : expr_app expr_select + { $$ = new ExprApp(CUR_POS, $1, $2); } + | expr_select { $$ = $1; } + ; + +expr_select + : expr_simple '.' attrpath + { $$ = new ExprSelect(CUR_POS, $1, *$3, 0); } + | expr_simple '.' attrpath OR_KW expr_select + { $$ = new ExprSelect(CUR_POS, $1, *$3, $5); } + | /* Backwards compatibility: because Nixpkgs has a rarely used + function named ‘or’, allow stuff like ‘map or [...]’. */ + expr_simple OR_KW + { $$ = new ExprApp(CUR_POS, $1, new ExprVar(CUR_POS, data->symbols.Create("or"))); } + | expr_simple { $$ = $1; } + ; + +expr_simple + : ID { + if (strcmp($1, "__curPos") == 0) + $$ = new ExprPos(CUR_POS); + else + $$ = new ExprVar(CUR_POS, data->symbols.Create($1)); + } + | INT { $$ = new ExprInt($1); } + | FLOAT { $$ = new ExprFloat($1); } + | '"' string_parts '"' { $$ = $2; } + | IND_STRING_OPEN ind_string_parts IND_STRING_CLOSE { + $$ = stripIndentation(CUR_POS, data->symbols, *$2); + } + | PATH { $$ = new ExprPath(absPath($1, data->basePath)); } + | HPATH { $$ = new ExprPath(getHome() + std::string{$1 + 1}); } + | SPATH { + std::string path($1 + 1, strlen($1) - 2); + $$ = new ExprApp(CUR_POS, + new ExprApp(new ExprVar(data->symbols.Create("__findFile")), + new ExprVar(data->symbols.Create("__nixPath"))), + new ExprString(data->symbols.Create(path))); + } + | URI { $$ = new ExprString(data->symbols.Create($1)); } + | '(' expr ')' { $$ = $2; } + /* Let expressions `let {..., body = ...}' are just desugared + into `(rec {..., body = ...}).body'. */ + | LET '{' binds '}' + { $3->recursive = true; $$ = new ExprSelect(noPos, $3, data->symbols.Create("body")); } + | REC '{' binds '}' + { $3->recursive = true; $$ = $3; } + | '{' binds '}' + { $$ = $2; } + | '[' expr_list ']' { $$ = $2; } + ; + +string_parts + : STR + | string_parts_interpolated { $$ = new ExprConcatStrings(CUR_POS, true, $1); } + | { $$ = new ExprString(data->symbols.Create("")); } + ; + +string_parts_interpolated + : string_parts_interpolated STR { $$ = $1; $1->push_back($2); } + | string_parts_interpolated DOLLAR_CURLY expr '}' { $$ = $1; $1->push_back($3); } + | DOLLAR_CURLY expr '}' { $$ = new nix::VectorExprs; $$->push_back($2); } + | STR DOLLAR_CURLY expr '}' { + $$ = new nix::VectorExprs; + $$->push_back($1); + $$->push_back($3); + } + ; + +ind_string_parts + : ind_string_parts IND_STR { $$ = $1; $1->push_back($2); } + | ind_string_parts DOLLAR_CURLY expr '}' { $$ = $1; $1->push_back($3); } + | { $$ = new nix::VectorExprs; } + ; + +binds + : binds attrpath '=' expr ';' { $$ = $1; addAttr($$, *$2, $4, makeCurPos(@2, data)); } + | binds INHERIT attrs ';' + { $$ = $1; + for (auto & i : *$3) { + auto sym = std::get<Symbol>(i); + if ($$->attrs.find(sym) != $$->attrs.end()) { + dupAttr(sym, makeCurPos(@3, data), $$->attrs[sym].pos); + } + Pos pos = makeCurPos(@3, data); + $$->attrs[sym] = ExprAttrs::AttrDef(new ExprVar(CUR_POS, sym), pos, true); + } + } + | binds INHERIT '(' expr ')' attrs ';' + { $$ = $1; + /* !!! Should ensure sharing of the expression in $4. */ + for (auto & i : *$6) { + auto sym = std::get<Symbol>(i); + if ($$->attrs.find(sym) != $$->attrs.end()) { + dupAttr(sym, makeCurPos(@6, data), $$->attrs[sym].pos); + } + $$->attrs[sym] = ExprAttrs::AttrDef(new ExprSelect(CUR_POS, $4, sym), makeCurPos(@6, data)); + } + } + | { $$ = new ExprAttrs; } + ; + +attrs + : attrs attr { $$ = $1; $1->push_back(AttrName(data->symbols.Create($2))); } + | attrs string_attr + { $$ = $1; + ExprString * str = dynamic_cast<ExprString *>($2); + if (str) { + $$->push_back(AttrName(str->s)); + delete str; + } else + throw ParseError(format("dynamic attributes not allowed in inherit at %1%") + % makeCurPos(@2, data)); + } + | { $$ = new AttrPath; } + ; + +attrpath + : attrpath '.' attr { $$ = $1; $1->push_back(AttrName(data->symbols.Create($3))); } + | attrpath '.' string_attr + { $$ = $1; + ExprString * str = dynamic_cast<ExprString *>($3); + if (str) { + $$->push_back(AttrName(str->s)); + delete str; + } else { + $$->push_back(AttrName($3)); + } + } + | attr { $$ = new nix::AttrNameVector; $$->push_back(AttrName(data->symbols.Create($1))); } + | string_attr + { $$ = new nix::AttrNameVector; + ExprString *str = dynamic_cast<ExprString *>($1); + if (str) { + $$->push_back(AttrName(str->s)); + delete str; + } else + $$->push_back(AttrName($1)); + } + ; + +attr + : ID { $$ = $1; } + | OR_KW { $$ = "or"; } + ; + +string_attr + : '"' string_parts '"' { $$ = $2; } + | DOLLAR_CURLY expr '}' { $$ = $2; } + ; + +expr_list + : expr_list expr_select { $$ = $1; $1->elems.push_back($2); /* !!! dangerous */ } + | { $$ = new ExprList; } + ; + +formals + : formal ',' formals + { $$ = $3; addFormal(CUR_POS, $$, *$1); } + | formal + { $$ = new Formals; addFormal(CUR_POS, $$, *$1); $$->ellipsis = false; } + | + { $$ = new Formals; $$->ellipsis = false; } + | ELLIPSIS + { $$ = new Formals; $$->ellipsis = true; } + ; + +formal + : ID { $$ = new Formal(data->symbols.Create($1), 0); } + | ID '?' expr { $$ = new Formal(data->symbols.Create($1), $3); } + ; + +%% + + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> + +#include "libexpr/eval.hh" +#include "libstore/store-api.hh" + + +namespace nix { + +Expr* EvalState::parse(const char* text, const Path& path, const Path& basePath, + StaticEnv& staticEnv) { + yyscan_t scanner; + ParseData data(*this); + data.basePath = basePath; + data.path = data.symbols.Create(path); + + yylex_init(&scanner); + yy_scan_string(text, scanner); + int res = yyparse(scanner, &data); + yylex_destroy(scanner); + + if (res) { + throw ParseError(data.error); + } + + data.result->bindVars(staticEnv); + + return data.result; +} + +} // namespace nix |