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Setting a leavestep trace on a command will not result in an error and is simply ignored. When the trace triggers, depending on the operations being traced, a number of When tclsh is called with no arguments, it starts in an interactive mode and displays a "%" prompt. Where type is command, execution, or variable. For leave and leavestep operations: command command-string code result op Command-string gives the complete current command being executed (the traced command for a enter operation, an arbitrary command for a enterstep http://colinmeldrum.com/tcl-error/tcl-error-stack-trace.html

Setting a leavestep trace on a command will not result in an error and is simply ignored. When the trace triggers, depending on the operations being traced, a number of DESCRIPTION trace add type name ops ?args? Tcl will always remove the command once the trace is complete. Better ideas welcome. http://stackoverflow.com/questions/2193731/stack-trace-info-in-errorinfo-in-tcl

Tcl Return Error

name may be just the name of an array, with no parenthesized index). Incomplete and subject to change at short notice, but something is better than nothing. :-)trythrowreturnArts and crafts of Tcl-Tk programmingCategory Command HomeRecent changesHelpWhoAmI/LogoutCreate new pageRandom pagePrevious pageNext pageAdd commentsEditHistoryEdit summaryReferences Page Returns an empty string. trace info type name Where type is either command, execution or variable.

If name doesn't have any traces set, then the result of the command will be an empty string. This results in a stack trace like so: Yup, an error while executing "error "Yup, an error"" (procedure "four" line 2) invoked from within "four" (procedure "three" line 2) invoked from trace add variable name ops command Arrange for command to be executed whenever variable name is accessed in one of the ways given by the list ops. Tcl Warning By using this site, you agree to the Terms of Use and Privacy Policy.

error $errMsg $savedInfo If the code argument is present, then its value is stored in the errorCode global variable. Tcl Error Handling If the variable does not exist, it will be created but will not be given a value, so it will be visible to namespace which queries, but not to info exists too hot!"} Where the error occurred is evident from::errorInfo, which will look a bit clearer (no mention of the error command) if you code if {$temperature > 100} {return -code error leavestep Invoke command for every tcl command which is executed inside the procedure name, just after the actual execution takes place.

If the info argument is present, it is used to initialize the -errorinfo return options and the first increment of unwind information will not be added by the Tcl interpreter. Tcl Errorinfo trace info variable name Returns a list containing one element for each trace currently set on variable name. If an error occurs while executing the command body, then the command name as a whole will return that same error. Each element of the list is itself a list containing two elements, which are the opList and command associated with the trace.

Tcl Error Handling

Ops indicates which operations are of interest, and is a list of one or more of the following items: rename Invoke command whenever the command is renamed. http://wiki.tcl.tk/16183 Name will be resolved using the usual namespace resolution rules used by procedures. Tcl Return Error If command modifies the value of a variable during a read or write trace, then the new value will be returned as the result of the traced operation. Tcl Error Code The trace operation can be used to stop the command from executing, by deleting the command in question.

delete Invoke command when the command is deleted. http://colinmeldrum.com/tcl-error/tcl-error-f5.html KEYWORDS error, errorCode, errorInfo Last change: [ tcl8.0a1 | tk8.0a1 | X-ref ] Copyright © 1989-1994 The Regents of the University of California. enterstep Invoke command for every tcl command which is executed inside the procedure name, just before the actual execution takes place. Here are some chained Tcl procs: proc one {} { two } proc two {} { three } proc three {} { four } proc four {} { error "Yup, an Tcl Error Command

Returns an empty string. If name doesn't exist, the command will throw an error. If name doesn't exist or doesn't have any traces set, then the result of the command will be an empty string. For backwards compatibility, three other subcommands are available: Check This Out While command is executing during an execution trace, traces on name are temporarily disabled.

tcl stack-trace share|improve this question edited Feb 5 '10 at 17:13 Trey Jackson 60.4k8151191 asked Feb 3 '10 at 17:02 ls. 125210 add a comment| 3 Answers 3 active oldest votes Tcl Throw Error However, if command unsets the variable then unset traces will be invoked. Variables can be unset explicitly with the unset command, or implicitly when procedures return (all of their local variables are unset).

Commands are also deleted when the interpreter is deleted, but traces will not be invoked because there is no interpreter in which to execute them. When the trace triggers, depending

When an unset trace is invoked, the variable has already been deleted: it will appear to be undefined with no traces. This allows the command to execute name in its body without invoking any other traces again. Both oldName and newName are fully qualified with any namespace(s) in which they appear. Tcl Stack Trace So in C, you have to add checks for everything that might go wrong; in Tcl, you only need to treat errors if you can express it better than Tcl already

trace info command name Returns a list containing one element for each trace currently set on command name. The return value from command is ignored except that if it returns an error of any sort then the traced operation also returns an error with the same error message returned If an error occurs while executing the command body, then the command name as a whole will return that same error. this contact form If command invokes a procedure (which it normally does) then the procedure will have to use upvar or uplevel commands if it wishes to access the local variables of the code

The problem is : in non-interactive mode when I want to catch this error and then puts the errorInfo to get a stack trace, it'll merely display the terse info. Stepping through a procedure[edit] To find out how exactly a proc works (and what goes wrong where), you can also register commands to be called before and after a command inside Variables can be unset explicitly with the unset command, or implicitly when procedures return (all of their local variables are unset). This means that reads and writes invoked by command will occur directly, without invoking command (or any other traces) again.

Name1 and name2 are not necessarily the same as the name used in the trace variable command: the upvar command allows a procedure to reference a variable under a different name. For example: console eval {.console config -font Times} will change the font of the console to "Times". To get information about commands, it makes sense to type the following: % info commands tell socket subst lremove open eof tkcon_tcl_gets pwd glob list exec pid echo dir auto_load_index time Recursive renaming or deleting will not cause further traces of the same type to be evaluated, so a delete trace which itself deletes the command, or a rename trace which itself

Ops indicates which operations are of interest, and is a list of one or more of the following items: rename Invoke command whenever the command is renamed. Of course when the command is subsequently executed, an 'invalid command' error will occur. Each element of the list is itself a list containing two elements, which are the opList and command associated with the trace. HesabımAramaHaritalarYouTubePlayHaberlerGmailDriveTakvimGoogle+ÇeviriFotoğraflarDaha fazlasıDokümanlarBloggerKişilerHangoutsGoogle'a ait daha da fazla uygulamaOturum açınGizli alanlarGrupları veya mesajları ara Tcl Programming/Debugging From Wikibooks, open books for an open world < Tcl ProgrammingThis page may need to be reviewed

The legal option's (which may be abbreviated) are: trace add type name ops ?args? Commands can be deleted explicitly by using the rename command to rename the command to an empty string. Op indicates what operation is being performed on the command execution, and is one of leave or leavestep as defined above. Is Einstein's theory really challenged by the recent paper in news?

You may make it really strict by adding an "exit" after the "puts stderr ...", or throw an error. The -errorcode return option is intended to hold a machine-readable description of the error in cases where such information is available; see the return manual page for information on the proper Binary to decimal converter Will Panharmonicon entering the battlefield duplicate ETBs it triggers? The trace operation can be used to stop the command from executing, by deleting the command in question.