.\" .\" Manual page for the js interpreter. .\" Copyright (c) 1998 New Generation Software (NGS) Oy .\" Author: Markku Rossi .\" .\" This library is free software; you can redistribute it and/or .\" modify it under the terms of the GNU Library General Public .\" License as published by the Free Software Foundation; either .\" version 2 of the License, or (at your option) any later version. .\" .\" This library is distributed in the hope that it will be useful, .\" but WITHOUT ANY WARRANTY; without even the implied warranty of .\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU .\" Library General Public License for more details. .\" .\" You should have received a copy of the GNU Library General Public .\" License along with this library; if not, write to the Free .\" Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, .\" MA 02111-1307, USA .\" .TH JS 1 "Sep 25, 1998" "JS" "JS" .SH NAME js \- interpret, execute, and compile JavaScript files .SH SYNOPSIS .B js [\f3\-acfghlNStvV\f1] [\f1\-d \f2type\f1] [\f1\-e \f2code\f1] [\f1\-O\f1[\f2level\f1]] [\f1\-r \f2option\f1] [\f1\-s \f2size\f1] [\f1\-W \f2option\f1] \f2file\f1 [\f2argument\f1]... .SH DESCRIPTION The \f3js\f1 program is the JavaScript interpreter command. It can be used to execute JavaScript and JavaScript byte-code files. The progam can also be used to compile JavaScript files into the byte-code files. .SH OPTIONS .TP 8 .B \-a, \-\-annotate\-assembler Annotate the created assembler listing with the original JavaScript source code. The option can be used only with the \f3\-\-assembler\f1 option. .TP 8 .B \-c, \-\-compile Compile JavaScript files to byte\-code. The generated byte\-code is saved to file which name is created from the name of the input file by replacing the suffix \f3.js\f1 with the suffix \f3.jsc\f1. The compilation can be controlled with options \f3\-\-debug\f1, \f3\-\-optimize\f1, and \f3\-\-compiler-option\f1. .TP 8 .B \-d \f2type\f3, \-\-dispatch=\f2type\f3 Use the byte-code instruction dispatch method \f2type\f1. The current implementation supports the following dispatch methods: .RS 8 .TP 8 .B switch\-basic The basic switch-method using a big switch-case table to dispatch the instruction. This method is available only if the interpreter has been configured with the option \f3\-\-with\-all\-dispatchers\f1. .TP 8 .B switch An optimized version of the switch\-method. This method is supported on all environments. .TP .B jumps The fastest dispatch method that uses the `computed goto' statement of the GNU C\-compiler. This method is available if the interpreter has been compiled with the GNU C\-compiler. .RE The default dispatch method, for environments that has the GNU C-compiler, is \f3jumps\f1. For all other environments, the default method is \f3switch\f1. .TP .B \-e \f2code\f1, \-\-eval=\f2code\f3 Evaluate JavaScript code \f2code\f1. .TP .B \-f, \-\-file Stop processing options and use the next argument as the name of the JavaScript (or byte\-code) file. All the remaining arguments are passed to the interpreter through the \f3ARGS\f1 array. The first item of the array will be the name of the script, i.e. the argument that follows the option \f3\-\-file\f1. .TP .B \-g, \-\-debug Make the compiler to generate debugging information to the generated byte\-code files. This option can be used with the option \f3\-\-compile\f1. .TP .B \-h, \-\-help Print a short help message that describes the options that can be given to the \f3js\f1 program. .TP .B \-l, \-\-load Load multiple JavaScript and JavaScript byte\-code files to the interpreter. Normally, the first non\-option argument is evaluated and all remaining arguments are passed to the script as arguments. With the option \f3\-\-load\f1, multiple files can be loaded the to the interpreter. The loading can be stopped with option \f3\-\-file\f1 that specifies the last file to load. .TP .B \-N, \-\-no\-compiler Do not define the compiler to the virtual machine. This option makes the interpreter smaller, but the interpreter can only execute pre\-compiled byte\-code files. The option disables the \f3eval\f1 global method. .TP .B \-O \f1[\f2level\f1]\f3, \-\-optimize\f1[\f3=\f2level\f1]\f3 Set the compiler optimization level to \f2level\f1. The compiler has three different optimization levels: .RS 8 .TP 8 .B 0 Do not optimize. .TP 8 .B 1 Perform all cheap optimizations which do not required heavy assembler instruction analyzing. .TP 8 .B 2 Perform all optimizations, supported by the compiler. .RE The default optimization level is 1. .TP .B \-r \f2option\f3, \-\-secure=\f2option\f3 Turn on virtual machine security option \f2option\f1. The following security options are available: .RS 8 .TP 8 .B file Disable insecure methods from the buit-in File object. .TP 8 .B system Disable insecure methods from the buit-in System object. .RE .TP .B \-s \f2size\f3, \-\-stack\-size=\f2size\f3 Set the size of the virtual machine operand stack to \f2size\f1. The size of the virtual machine operand stack is set at the startup\-time and it can't be enlarged dynamically at the runtime. .TP .B \-S, \-\-assembler Compile JavaScript files to JavaScript assembler. The generated assembler listing is saved to file which name is created from the name of the input file by replacing the suffix \f3.js\f1 with the suffix \f3.jas\f1. The compilation can be controlled with options \f3\-\-optimize\f1, and \f3\-\-compiler\-option\f1. .TP .B \-t, \-\-stacktrace Print a stack trace on error. When an error occurs during the evaluation of a script, the virtual machine will halt and the \f3js\f1 program terminates. If the option \f3\-\-stacktrace\f1 was given to the interpreter, the virtual machine will print a stack trace that shows the call stack at the point of the error. .TP .B \-v, \-\-verbose Increase the verbosity of the interpreter. The option can be given multiple times to increase the amount of messages the interpreter prints. .TP .B \-V, \-\-version Print the version number of the \f3js\f1 program. .TP .B \-W \f3option\f3, \-\-compiler\-option=\f2option\f3 Set JavaScript compiler options according to the option specification \f2option\f1. The specification \f2option\f1 can be given in two forms. In the normal form, the option specifies a compiler option that should be set on. If the specification @var{option} starts with the prefix `\f3no-\f1', the specified option will be turn off. The following option specifications are currently implemented: .RS 8 .TP 8 .B all match most of the compile time options .TP 8 .B pedantic match all compile time options. This option generates as much warnings as possible. It will also complain about some things that are allowed by the ECMAScript standard, but which are consired to show bad programming style, for example, missing semicolons. .TP 8 .B runtime match all runtime options .TP 8 .B shadow warn if a variable declaration shadows a parameter .TP 8 .B undefined runtime check for undefined global variables .TP 8 .B unused\-argument warn about unused arguments .TP 8 .B unused-variable warn about unused local variables .TP 8 .B with\-clobber warn if the with\-lookup of a symbol is clobbered because the symbol is defined to be a local variable or a function argument .TP 8 .B missing\-semicolon warn about missing semicolons that are fixed by the missing semicolon inserting during the compilation .TP 8 .B strict\-ecma warn about things that are supported by this implementation, but are not allowed by the ECMAScript standard. These features are: .RS 8 .TP 2 \- line terminators in string and regular expression constant .RE .TP 8 .B deprecated warn if deprecated features has been used in the source code .RE .TP 8 .B \-x, \-\-executable Add execute permissions to the generated byte-code files. This option is useful on Linux environments where JavaScript byte-code files can be executed natively with the `binfmt_js' module. .SH AUTHOR Markku Rossi NGS JavaScript WWW home page: .SH SEE ALSO jsdas(1)