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diff --git a/tcl8.6/doc/info.n b/tcl8.6/doc/info.n new file mode 100644 index 0000000..1ad908d --- /dev/null +++ b/tcl8.6/doc/info.n @@ -0,0 +1,777 @@ +'\" +'\" Copyright (c) 1993 The Regents of the University of California. +'\" Copyright (c) 1994-1997 Sun Microsystems, Inc. +'\" Copyright (c) 1993-1997 Bell Labs Innovations for Lucent Technologies +'\" Copyright (c) 1998-2000 Ajuba Solutions +'\" Copyright (c) 2007-2012 Donal K. Fellows +'\" +'\" See the file "license.terms" for information on usage and redistribution +'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. +'\" +.TH info n 8.4 Tcl "Tcl Built-In Commands" +.so man.macros +.BS +'\" Note: do not modify the .SH NAME line immediately below! +.SH NAME +info \- Return information about the state of the Tcl interpreter +.SH SYNOPSIS +\fBinfo \fIoption \fR?\fIarg arg ...\fR? +.BE +.SH DESCRIPTION +.PP +This command provides information about various internals of the Tcl +interpreter. +The legal \fIoption\fRs (which may be abbreviated) are: +.TP +\fBinfo args \fIprocname\fR +. +Returns a list containing the names of the arguments to procedure +\fIprocname\fR, in order. \fIProcname\fR must be the name of a +Tcl command procedure. +.TP +\fBinfo body \fIprocname\fR +. +Returns the body of procedure \fIprocname\fR. \fIProcname\fR must be +the name of a Tcl command procedure. +.TP +\fBinfo class\fI subcommand class\fR ?\fIarg ...\fR +.VS 8.6 +Returns information about the class, \fIclass\fR. The \fIsubcommand\fRs are +described in \fBCLASS INTROSPECTION\fR below. +.VE 8.6 +.TP +\fBinfo cmdcount\fR +. +Returns a count of the total number of commands that have been invoked +in this interpreter. +.TP +\fBinfo commands \fR?\fIpattern\fR? +. +If \fIpattern\fR is not specified, +returns a list of names of all the Tcl commands visible +(i.e. executable without using a qualified name) to the current namespace, +including both the built-in commands written in C and +the command procedures defined using the \fBproc\fR command. +If \fIpattern\fR is specified, +only those names matching \fIpattern\fR are returned. +Matching is determined using the same rules as for \fBstring match\fR. +\fIpattern\fR can be a qualified name like \fBFoo::print*\fR. +That is, it may specify a particular namespace +using a sequence of namespace names separated by double colons (\fB::\fR), +and may have pattern matching special characters +at the end to specify a set of commands in that namespace. +If \fIpattern\fR is a qualified name, +the resulting list of command names has each one qualified with the name +of the specified namespace, and only the commands defined in the named +namespace are returned. +.\" Technically, most of this hasn't changed; that's mostly just the +.\" way it always worked. Hardly anyone knew that though. +.TP +\fBinfo complete \fIcommand\fR +. +Returns 1 if \fIcommand\fR is a complete Tcl command in the sense of +having no unclosed quotes, braces, brackets or array element names. +If the command does not appear to be complete then 0 is returned. +This command is typically used in line-oriented input environments +to allow users to type in commands that span multiple lines; if the +command is not complete, the script can delay evaluating it until additional +lines have been typed to complete the command. +.TP +\fBinfo coroutine\fR +.VS 8.6 +Returns the name of the currently executing \fBcoroutine\fR, or the empty +string if either no coroutine is currently executing, or the current coroutine +has been deleted (but has not yet returned or yielded since deletion). +.VE 8.6 +.TP +\fBinfo default \fIprocname arg varname\fR +. +\fIProcname\fR must be the name of a Tcl command procedure and \fIarg\fR +must be the name of an argument to that procedure. If \fIarg\fR +does not have a default value then the command returns \fB0\fR. +Otherwise it returns \fB1\fR and places the default value of \fIarg\fR +into variable \fIvarname\fR. +.TP +\fBinfo errorstack \fR?\fIinterp\fR? +.VS 8.6 +Returns, in a form that is programmatically easy to parse, the function names +and arguments at each level from the call stack of the last error in the given +\fIinterp\fR, or in the current one if not specified. +.RS +.PP +This form is an even-sized list alternating tokens and parameters. Tokens are +currently either \fBCALL\fR, \fBUP\fR, or \fBINNER\fR, but other values may be +introduced in the future. \fBCALL\fR indicates a procedure call, and its +parameter is the corresponding \fBinfo level\fR \fB0\fR. \fBUP\fR indicates a +shift in variable frames generated by \fBuplevel\fR or similar, and applies to +the previous \fBCALL\fR item. Its parameter is the level offset. \fBINNER\fR +identifies the +.QW "inner context" , +which is the innermost atomic command or bytecode instruction that raised the +error, along with its arguments when available. While \fBCALL\fR and \fBUP\fR +allow to follow complex call paths, \fBINNER\fR homes in on the offending +operation in the innermost procedure call, even going to sub-expression +granularity. +.PP +This information is also present in the \fB\-errorstack\fR entry of the +options dictionary returned by 3-argument \fBcatch\fR; \fBinfo errorstack\fR +is a convenient way of retrieving it for uncaught errors at top-level in an +interactive \fBtclsh\fR. +.RE +.VE 8.6 +.TP +\fBinfo exists \fIvarName\fR +. +Returns \fB1\fR if the variable named \fIvarName\fR exists in the +current context (either as a global or local variable) and has been +defined by being given a value, returns \fB0\fR otherwise. +.TP +\fBinfo frame\fR ?\fInumber\fR? +. +This command provides access to all frames on the stack, even those +hidden from \fBinfo level\fR. If \fInumber\fR is not specified, this +command returns a number giving the frame level of the command. This +is 1 if the command is invoked at top-level. If \fInumber\fR is +specified, then the result is a dictionary containing the location +information for the command at the \fInumber\fRed level on the stack. +.RS +.PP +If \fInumber\fR is positive (> 0) then it selects a particular stack +level (1 refers to the outer-most active command, 2 to the command it +called, and so on, up to the current frame level which refers to +\fBinfo frame\fR itself); otherwise it gives a level relative to the +current command (0 refers to the current command, i.e., \fBinfo +frame\fR itself, -1 to its caller, and so on). +.PP +This is similar to how \fBinfo level\fR works, except that this +subcommand reports all frames, like \fBsource\fRd scripts, +\fBeval\fRs, \fBuplevel\fRs, etc. +.PP +Note that for nested commands, like +.QW "foo [bar [x]]" , +only +.QW x +will be seen by an \fBinfo frame\fR invoked within +.QW x . +This is the same as for \fBinfo level\fR and error stack traces. +.PP +The result dictionary may contain the keys listed below, with the +specified meanings for their values: +.TP +\fBtype\fR +. +This entry is always present and describes the nature of the location +for the command. The recognized values are \fBsource\fR, \fBproc\fR, +\fBeval\fR, and \fBprecompiled\fR. +.RS +.TP +\fBsource\fR\0\0\0\0\0\0\0\0 +. +means that the command is found in a script loaded by the \fBsource\fR +command. +.TP +\fBproc\fR\0\0\0\0\0\0\0\0 +. +means that the command is found in dynamically created procedure body. +.TP +\fBeval\fR\0\0\0\0\0\0\0\0 +. +means that the command is executed by \fBeval\fR or \fBuplevel\fR. +.TP +\fBprecompiled\fR\0\0\0\0\0\0\0\0 +. +means that the command is found in a pre-compiled script (loadable by +the package \fBtbcload\fR), and no further information will be +available. +.RE +.TP +\fBline\fR +. +This entry provides the number of the line the command is at inside of +the script it is a part of. This information is not present for type +\fBprecompiled\fR. For type \fBsource\fR this information is counted +relative to the beginning of the file, whereas for the last two types +the line is counted relative to the start of the script. +.TP +\fBfile\fR +. +This entry is present only for type \fBsource\fR. It provides the +normalized path of the file the command is in. +.TP +\fBcmd\fR +. +This entry provides the string representation of the command. This is +usually the unsubstituted form, however for commands which are a +canonically-constructed list (e.g., as produced by the \fBlist\fR command) +executed by \fBeval\fR it is the substituted form as they have no other +string representation. Care is taken that the canonicality property of +the latter is not spoiled. +.TP +\fBproc\fR +. +This entry is present only if the command is found in the body of a +regular Tcl procedure. It then provides the name of that procedure. +.TP +\fBlambda\fR +. +This entry is present only if the command is found in the body of an +anonymous Tcl procedure, i.e. a lambda. It then provides the entire +definition of the lambda in question. +.TP +\fBlevel\fR +. +This entry is present only if the queried frame has a corresponding +frame returned by \fBinfo level\fR. It provides the index of this +frame, relative to the current level (0 and negative numbers). +.PP +A thing of note is that for procedures statically defined in files the +locations of commands in their bodies will be reported with type +\fBsource\fR and absolute line numbers, and not as type +\fBproc\fR. The same is true for procedures nested in statically +defined procedures, and literal eval scripts in files or statically +defined procedures. +.PP +In contrast, procedure definitions and \fBeval\fR within a dynamically +\fBeval\fRuated environment count line numbers relative to the start of +their script, even if they would be able to count relative to the +start of the outer dynamic script. That type of number usually makes +more sense. +.PP +A different way of describing this behaviour is that file based +locations are tracked as deeply as possible, and where this is not +possible the lines are counted based on the smallest possible +\fBeval\fR or procedure body, as that scope is usually easier to find +than any dynamic outer scope. +.PP +The syntactic form \fB{*}\fR is handled like \fBeval\fR. I.e. if it +is given a literal list argument the system tracks the line number +within the list words as well, and otherwise all line numbers are +counted relative to the start of each word (smallest scope) +.RE +.TP +\fBinfo functions \fR?\fIpattern\fR? +. +If \fIpattern\fR is not specified, returns a list of all the math +functions currently defined. +If \fIpattern\fR is specified, only those functions whose name matches +\fIpattern\fR are returned. Matching is determined using the same +rules as for \fBstring match\fR. +.TP +\fBinfo globals \fR?\fIpattern\fR? +. +If \fIpattern\fR is not specified, returns a list of all the names +of currently-defined global variables. +Global variables are variables in the global namespace. +If \fIpattern\fR is specified, only those names matching \fIpattern\fR +are returned. Matching is determined using the same rules as for +\fBstring match\fR. +.TP +\fBinfo hostname\fR +. +Returns the name of the computer on which this invocation is being +executed. +Note that this name is not guaranteed to be the fully qualified domain +name of the host. Where machines have several different names (as is +common on systems with both TCP/IP (DNS) and NetBIOS-based networking +installed,) it is the name that is suitable for TCP/IP networking that +is returned. +.TP +\fBinfo level\fR ?\fInumber\fR? +. +If \fInumber\fR is not specified, this command returns a number +giving the stack level of the invoking procedure, or 0 if the +command is invoked at top-level. If \fInumber\fR is specified, +then the result is a list consisting of the name and arguments for the +procedure call at level \fInumber\fR on the stack. If \fInumber\fR +is positive then it selects a particular stack level (1 refers +to the top-most active procedure, 2 to the procedure it called, and +so on); otherwise it gives a level relative to the current level +(0 refers to the current procedure, -1 to its caller, and so on). +See the \fBuplevel\fR command for more information on what stack +levels mean. +.TP +\fBinfo library\fR +. +Returns the name of the library directory in which standard Tcl +scripts are stored. +This is actually the value of the \fBtcl_library\fR +variable and may be changed by setting \fBtcl_library\fR. +.TP +\fBinfo loaded \fR?\fIinterp\fR? +. +Returns a list describing all of the packages that have been loaded into +\fIinterp\fR with the \fBload\fR command. +Each list element is a sub-list with two elements consisting of the +name of the file from which the package was loaded and the name of +the package. +For statically-loaded packages the file name will be an empty string. +If \fIinterp\fR is omitted then information is returned for all packages +loaded in any interpreter in the process. +To get a list of just the packages in the current interpreter, specify +an empty string for the \fIinterp\fR argument. +.TP +\fBinfo locals \fR?\fIpattern\fR? +. +If \fIpattern\fR is not specified, returns a list of all the names +of currently-defined local variables, including arguments to the +current procedure, if any. +Variables defined with the \fBglobal\fR, \fBupvar\fR and +\fBvariable\fR commands will not be returned. +If \fIpattern\fR is specified, only those names matching \fIpattern\fR +are returned. Matching is determined using the same rules as for +\fBstring match\fR. +.TP +\fBinfo nameofexecutable\fR +. +Returns the full path name of the binary file from which the application +was invoked. If Tcl was unable to identify the file, then an empty +string is returned. +.TP +\fBinfo object\fI subcommand object\fR ?\fIarg ...\fR +.VS 8.6 +Returns information about the object, \fIobject\fR. The \fIsubcommand\fRs are +described in \fBOBJECT INTROSPECTION\fR below. +.VE 8.6 +.TP +\fBinfo patchlevel\fR +. +Returns the value of the global variable \fBtcl_patchLevel\fR, which holds +the exact version of the Tcl library by default. +.TP +\fBinfo procs \fR?\fIpattern\fR? +. +If \fIpattern\fR is not specified, returns a list of all the +names of Tcl command procedures in the current namespace. +If \fIpattern\fR is specified, +only those procedure names in the current namespace +matching \fIpattern\fR are returned. +Matching is determined using the same rules as for +\fBstring match\fR. +If \fIpattern\fR contains any namespace separators, they are used to +select a namespace relative to the current namespace (or relative to +the global namespace if \fIpattern\fR starts with \fB::\fR) to match +within; the matching pattern is taken to be the part after the last +namespace separator. +.TP +\fBinfo script\fR ?\fIfilename\fR? +. +If a Tcl script file is currently being evaluated (i.e. there is a +call to \fBTcl_EvalFile\fR active or there is an active invocation +of the \fBsource\fR command), then this command returns the name +of the innermost file being processed. If \fIfilename\fR is specified, +then the return value of this command will be modified for the +duration of the active invocation to return that name. This is +useful in virtual file system applications. +Otherwise the command returns an empty string. +.TP +\fBinfo sharedlibextension\fR +. +Returns the extension used on this platform for the names of files +containing shared libraries (for example, \fB.so\fR under Solaris). +If shared libraries are not supported on this platform then an empty +string is returned. +.TP +\fBinfo tclversion\fR +. +Returns the value of the global variable \fBtcl_version\fR, which holds the +major and minor version of the Tcl library by default. +.TP +\fBinfo vars\fR ?\fIpattern\fR? +. +If \fIpattern\fR is not specified, +returns a list of all the names of currently-visible variables. +This includes locals and currently-visible globals. +If \fIpattern\fR is specified, only those names matching \fIpattern\fR +are returned. Matching is determined using the same rules as for +\fBstring match\fR. +\fIpattern\fR can be a qualified name like \fBFoo::option*\fR. +That is, it may specify a particular namespace +using a sequence of namespace names separated by double colons (\fB::\fR), +and may have pattern matching special characters +at the end to specify a set of variables in that namespace. +If \fIpattern\fR is a qualified name, +the resulting list of variable names +has each matching namespace variable qualified with the name +of its namespace. +Note that a currently-visible variable may not yet +.QW exist +if it has not +been set (e.g. a variable declared but not set by \fBvariable\fR). +.SS "CLASS INTROSPECTION" +.VS 8.6 +.PP +The following \fIsubcommand\fR values are supported by \fBinfo class\fR: +.VE 8.6 +.TP +\fBinfo class call\fI class method\fR +.VS +Returns a description of the method implementations that are used to provide a +stereotypical instance of \fIclass\fR's implementation of \fImethod\fR +(stereotypical instances being objects instantiated by a class without having +any object-specific definitions added). This consists of a list of lists of +four elements, where each sublist consists of a word that describes the +general type of method implementation (being one of \fBmethod\fR for an +ordinary method, \fBfilter\fR for an applied filter, and \fBunknown\fR for a +method that is invoked as part of unknown method handling), a word giving the +name of the particular method invoked (which is always the same as +\fImethod\fR for the \fBmethod\fR type, and +.QW \fBunknown\fR +for the \fBunknown\fR type), a word giving the fully qualified name of the +class that defined the method, and a word describing the type of method +implementation (see \fBinfo class methodtype\fR). +.RS +.PP +Note that there is no inspection of whether the method implementations +actually use \fBnext\fR to transfer control along the call chain. +.RE +.VE 8.6 +.TP +\fBinfo class constructor\fI class\fR +.VS 8.6 +This subcommand returns a description of the definition of the constructor of +class \fIclass\fR. The definition is described as a two element list; the first +element is the list of arguments to the constructor in a form suitable for +passing to another call to \fBproc\fR or a method definition, and the second +element is the body of the constructor. If no constructor is present, this +returns the empty list. +.VE 8.6 +.TP +\fBinfo class definition\fI class method\fR +.VS 8.6 +This subcommand returns a description of the definition of the method named +\fImethod\fR of class \fIclass\fR. The definition is described as a two element +list; the first element is the list of arguments to the method in a form +suitable for passing to another call to \fBproc\fR or a method definition, and +the second element is the body of the method. +.VE 8.6 +.TP +\fBinfo class destructor\fI class\fR +.VS 8.6 +This subcommand returns the body of the destructor of class \fIclass\fR. If no +destructor is present, this returns the empty string. +.VE 8.6 +.TP +\fBinfo class filters\fI class\fR +.VS 8.6 +This subcommand returns the list of filter methods set on the class. +.VE 8.6 +.TP +\fBinfo class forward\fI class method\fR +.VS 8.6 +This subcommand returns the argument list for the method forwarding called +\fImethod\fR that is set on the class called \fIclass\fR. +.VE 8.6 +.TP +\fBinfo class instances\fI class\fR ?\fIpattern\fR? +.VS 8.6 +This subcommand returns a list of instances of class \fIclass\fR. If the +optional \fIpattern\fR argument is present, it constrains the list of returned +instances to those that match it according to the rules of \fBstring match\fR. +.VE 8.6 +.TP +\fBinfo class methods\fI class\fR ?\fIoptions...\fR? +.VS 8.6 +This subcommand returns a list of all public (i.e. exported) methods of the +class called \fIclass\fR. Any of the following \fIoption\fRs may be +specified, controlling exactly which method names are returned: +.RS +.VE 8.6 +.TP +\fB\-all\fR +.VS 8.6 +If the \fB\-all\fR flag is given, the list of methods will include those +methods defined not just by the class, but also by the class's superclasses +and mixins. +.VE 8.6 +.TP +\fB\-private\fR +.VS 8.6 +If the \fB\-private\fR flag is given, the list of methods will also include +the private (i.e. non-exported) methods of the class (and superclasses and +mixins, if \fB\-all\fR is also given). +.RE +.VE 8.6 +.TP +\fBinfo class methodtype\fI class method\fR +.VS 8.6 +This subcommand returns a description of the type of implementation used for +the method named \fImethod\fR of class \fIclass\fR. When the result is +\fBmethod\fR, further information can be discovered with \fBinfo class +definition\fR, and when the result is \fBforward\fR, further information can +be discovered with \fBinfo class forward\fR. +.VE 8.6 +.TP +\fBinfo class mixins\fI class\fR +.VS 8.6 +This subcommand returns a list of all classes that have been mixed into the +class named \fIclass\fR. +.VE 8.6 +.TP +\fBinfo class subclasses\fI class\fR ?\fIpattern\fR? +.VS 8.6 +This subcommand returns a list of direct subclasses of class \fIclass\fR. If +the optional \fIpattern\fR argument is present, it constrains the list of +returned classes to those that match it according to the rules of +\fBstring match\fR. +.VE 8.6 +.TP +\fBinfo class superclasses\fI class\fR +.VS 8.6 +This subcommand returns a list of direct superclasses of class \fIclass\fR in +inheritance precedence order. +.VE 8.6 +.TP +\fBinfo class variables\fI class\fR +.VS 8.6 +This subcommand returns a list of all variables that have been declared for +the class named \fIclass\fR (i.e. that are automatically present in the +class's methods, constructor and destructor). +.SS "OBJECT INTROSPECTION" +.PP +The following \fIsubcommand\fR values are supported by \fBinfo object\fR: +.VE 8.6 +.TP +\fBinfo object call\fI object method\fR +.VS 8.6 +Returns a description of the method implementations that are used to provide +\fIobject\fR's implementation of \fImethod\fR. This consists of a list of +lists of four elements, where each sublist consists of a word that describes +the general type of method implementation (being one of \fBmethod\fR for an +ordinary method, \fBfilter\fR for an applied filter, and \fBunknown\fR for a +method that is invoked as part of unknown method handling), a word giving the +name of the particular method invoked (which is always the same as +\fImethod\fR for the \fBmethod\fR type, and +.QW \fBunknown\fR +for the \fBunknown\fR type), a word giving what defined the method (the fully +qualified name of the class, or the literal string \fBobject\fR if the method +implementation is on an instance), and a word describing the type of method +implementation (see \fBinfo object methodtype\fR). +.RS +.PP +Note that there is no inspection of whether the method implementations +actually use \fBnext\fR to transfer control along the call chain. +.RE +.VE 8.6 +.TP +\fBinfo object class\fI object\fR ?\fIclassName\fR? +.VS 8.6 +If \fIclassName\fR is unspecified, this subcommand returns class of the +\fIobject\fR object. If \fIclassName\fR is present, this subcommand returns a +boolean value indicating whether the \fIobject\fR is of that class. +.VE 8.6 +.TP +\fBinfo object definition\fI object method\fR +.VS 8.6 +This subcommand returns a description of the definition of the method named +\fImethod\fR of object \fIobject\fR. The definition is described as a two +element list; the first element is the list of arguments to the method in a +form suitable for passing to another call to \fBproc\fR or a method definition, +and the second element is the body of the method. +.VE 8.6 +.TP +\fBinfo object filters\fI object\fR +.VS 8.6 +This subcommand returns the list of filter methods set on the object. +.VE 8.6 +.TP +\fBinfo object forward\fI object method\fR +.VS 8.6 +This subcommand returns the argument list for the method forwarding called +\fImethod\fR that is set on the object called \fIobject\fR. +.VE 8.6 +.TP +\fBinfo object isa\fI category object\fR ?\fIarg\fR? +.VS 8.6 +This subcommand tests whether an object belongs to a particular category, +returning a boolean value that indicates whether the \fIobject\fR argument +meets the criteria for the category. The supported categories are: +.VE 8.6 +.RS +.TP +\fBinfo object isa class\fI object\fR +.VS 8.6 +This returns whether \fIobject\fR is a class (i.e. an instance of +\fBoo::class\fR or one of its subclasses). +.VE 8.6 +.TP +\fBinfo object isa metaclass\fI object\fR +.VS 8.6 +This returns whether \fIobject\fR is a class that can manufacture classes +(i.e. is \fBoo::class\fR or a subclass of it). +.VE 8.6 +.TP +\fBinfo object isa mixin\fI object class\fR +.VS 8.6 +This returns whether \fIclass\fR is directly mixed into \fIobject\fR. +.VE 8.6 +.TP +\fBinfo object isa object\fI object\fR +.VS 8.6 +This returns whether \fIobject\fR really is an object. +.VE 8.6 +.TP +\fBinfo object isa typeof\fI object class\fR +.VS 8.6 +This returns whether \fIclass\fR is the type of \fIobject\fR (i.e. whether +\fIobject\fR is an instance of \fIclass\fR or one of its subclasses, whether +direct or indirect). +.RE +.VE 8.6 +.TP +\fBinfo object methods\fI object\fR ?\fIoption...\fR? +.VS 8.6 +This subcommand returns a list of all public (i.e. exported) methods of the +object called \fIobject\fR. Any of the following \fIoption\fRs may be +specified, controlling exactly which method names are returned: +.RS +.VE 8.6 +.TP +\fB\-all\fR +.VS 8.6 +If the \fB\-all\fR flag is given, the list of methods will include those +methods defined not just by the object, but also by the object's class and +mixins, plus the superclasses of those classes. +.VE 8.6 +.TP +\fB\-private\fR +.VS 8.6 +If the \fB\-private\fR flag is given, the list of methods will also include +the private (i.e. non-exported) methods of the object (and classes, if +\fB\-all\fR is also given). +.RE +.VE 8.6 +.TP +\fBinfo object methodtype\fI object method\fR +.VS 8.6 +This subcommand returns a description of the type of implementation used for +the method named \fImethod\fR of object \fIobject\fR. When the result is +\fBmethod\fR, further information can be discovered with \fBinfo object +definition\fR, and when the result is \fBforward\fR, further information can +be discovered with \fBinfo object forward\fR. +.VE 8.6 +.TP +\fBinfo object mixins\fI object\fR +.VS 8.6 +This subcommand returns a list of all classes that have been mixed into the +object named \fIobject\fR. +.VE 8.6 +.TP +\fBinfo object namespace\fI object\fR +.VS 8.6 +This subcommand returns the name of the internal namespace of the object named +\fIobject\fR. +.VE 8.6 +.TP +\fBinfo object variables\fI object\fR +.VS 8.6 +This subcommand returns a list of all variables that have been declared for +the object named \fIobject\fR (i.e. that are automatically present in the +object's methods). +.VE 8.6 +.TP +\fBinfo object vars\fI object\fR ?\fIpattern\fR? +.VS 8.6 +This subcommand returns a list of all variables in the private namespace of +the object named \fIobject\fR. If the optional \fIpattern\fR argument is +given, it is a filter (in the syntax of a \fBstring match\fR glob pattern) +that constrains the list of variables returned. Note that this is different +from the list returned by \fBinfo object variables\fR; that can include +variables that are currently unset, whereas this can include variables that +are not automatically included by any of \fIobject\fR's methods (or those of +its class, superclasses or mixins). +.VE 8.6 +.SH EXAMPLES +.PP +This command prints out a procedure suitable for saving in a Tcl +script: +.PP +.CS +proc printProc {procName} { + set result [list proc $procName] + set formals {} + foreach var [\fBinfo args\fR $procName] { + if {[\fBinfo default\fR $procName $var def]} { + lappend formals [list $var $def] + } else { + # Still need the list-quoting because variable + # names may properly contain spaces. + lappend formals [list $var] + } + } + puts [lappend result $formals [\fBinfo body\fR $procName]] +} +.CE +.SS "EXAMPLES WITH OBJECTS" +.VS 8.6 +.PP +Every object necessarily knows what its class is; this information is +trivially extractable through introspection: +.PP +.CS +oo::class create c +c create o +puts [\fBinfo object class\fR o] + \fI\(-> prints "::c"\fR +puts [\fBinfo object class\fR c] + \fI\(-> prints "::oo::class"\fR +.CE +.PP +The introspection capabilities can be used to discover what class implements a +method and get how it is defined. This procedure illustrates how: +.PP +.CS +proc getDef {obj method} { + foreach inf [\fBinfo object call\fR $obj $method] { + lassign $inf calltype name locus methodtype + # Assume no forwards or filters, and hence no $calltype + # or $methodtype checks... + if {$locus eq "object"} { + return [\fBinfo object definition\fR $obj $name] + } else { + return [\fBinfo class definition\fR $locus $name] + } + } + error "no definition for $method" +} +.CE +.PP +This is an alternate way of looking up the definition; it is implemented by +manually scanning the list of methods up the inheritance tree. This code +assumes that only single inheritance is in use, and that there is no complex +use of mixed-in classes (in such cases, using \fBinfo object call\fR as above +is the simplest way of doing this by far): +.PP +.CS +proc getDef {obj method} { + if {$method in [\fBinfo object methods\fR $obj]} { + # Assume no forwards + return [\fBinfo object definition\fR $obj $method] + } + set cls [\fBinfo object class\fR $obj] + while {$method ni [\fBinfo class methods\fR $cls]} { + # Assume the simple case + set cls [lindex [\fBinfo class superclass\fR $cls] 0] + if {$cls eq ""} { + error "no definition for $method" + } + } + # Assume no forwards + return [\fBinfo class definition\fR $cls $method] +} +.CE +.VE 8.6 +.SH "SEE ALSO" +.VS 8.6 +global(n), oo::class(n), oo::define(n), oo::object(n), proc(n), self(n), +.VE 8.6 +tcl_library(n), tcl_patchLevel(n), tcl_version(n) +.SH KEYWORDS +command, information, interpreter, introspection, level, namespace, +.VS 8.6 +object, +.VE 8.6 +procedure, variable +'\" Local Variables: +'\" mode: nroff +'\" fill-column: 78 +'\" End: |