diff options
Diffstat (limited to 'doc/Eval.3')
| -rw-r--r-- | doc/Eval.3 | 76 |
1 files changed, 30 insertions, 46 deletions
@@ -5,7 +5,7 @@ '\" '\" See the file "license.terms" for information on usage and redistribution '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. -'\" +'\" .TH Tcl_Eval 3 8.1 Tcl "Tcl Library Procedures" .so man.macros .BS @@ -37,7 +37,7 @@ int \fBTcl_GlobalEvalObj\fR(\fIinterp, objPtr\fR) .sp int -\fBTcl_VarEval\fR(\fIinterp, part, part, ... \fB(char *)NULL\fR) +\fBTcl_VarEval\fR(\fIinterp, part, part, ... \fB(char *) NULL\fR) .sp int \fBTcl_VarEvalVA\fR(\fIinterp, argList\fR) @@ -47,17 +47,17 @@ int Interpreter in which to execute the script. The interpreter's result is modified to hold the result or error message from the script. .AP Tcl_Obj *objPtr in -A Tcl value containing the script to execute. +A Tcl object containing the script to execute. .AP int flags in -OR'ed combination of flag bits that specify additional options. +ORed combination of flag bits that specify additional options. \fBTCL_EVAL_GLOBAL\fR and \fBTCL_EVAL_DIRECT\fR are currently supported. .AP "const char" *fileName in Name of a file containing a Tcl script. .AP int objc in -The number of values in the array pointed to by \fIobjv\fR; +The number of objects in the array pointed to by \fIobjPtr\fR; this is also the number of words in the command. .AP Tcl_Obj **objv in -Points to an array of pointers to values; each value holds the +Points to an array of pointers to objects; each object holds the value of a single word in the command to execute. .AP int numBytes in The number of bytes in \fIscript\fR, not including any @@ -65,7 +65,7 @@ null terminating character. If \-1, then all characters up to the first null byte are used. .AP "const char" *script in Points to first byte of script to execute (null-terminated and UTF-8). -.AP "const char" *part in +.AP char *part in String forming part of a Tcl script. .AP va_list argList in An argument list which must have been initialized using @@ -83,7 +83,7 @@ If this is the first time \fIobjPtr\fR has been executed, its commands are compiled into bytecode instructions which are then executed. The bytecodes are saved in \fIobjPtr\fR so that the compilation step -can be skipped if the value is evaluated again in the future. +can be skipped if the object is evaluated again in the future. .PP The return value from \fBTcl_EvalObjEx\fR (and all the other procedures described here) is a Tcl completion code with @@ -99,25 +99,27 @@ its contents as a Tcl script. It returns the same information as If the file could not be read then a Tcl error is returned to describe why the file could not be read. The eofchar for files is -.QW \ex1A +.QW \e32 (^Z) for all platforms. If you require a .QW ^Z in code for string comparison, you can use -.QW \ex1A , +.QW \e032 +or +.QW \eu001a , which will be safely substituted by the Tcl interpreter into .QW ^Z . .PP -\fBTcl_EvalObjv\fR executes a single preparsed command instead of a +\fBTcl_EvalObjv\fR executes a single pre-parsed command instead of a script. The \fIobjc\fR and \fIobjv\fR arguments contain the values -of the words for the Tcl command, one word in each value in +of the words for the Tcl command, one word in each object in \fIobjv\fR. \fBTcl_EvalObjv\fR evaluates the command and returns a completion code and result just like \fBTcl_EvalObjEx\fR. The caller of \fBTcl_EvalObjv\fR has to manage the reference count of the -elements of \fIobjv\fR, insuring that the values are valid until -\fBTcl_EvalObjv\fR returns. +elements of \fIobjv\fR, insuring that the objects are valid until +\fBTcl_EvalObjv\fR returns. .PP \fBTcl_Eval\fR is similar to \fBTcl_EvalObjEx\fR except that the script to -be executed is supplied as a string instead of a value and no compilation +be executed is supplied as a string instead of an object and no compilation occurs. The string should be a proper UTF-8 string as converted by \fBTcl_ExternalToUtfDString\fR or \fBTcl_ExternalToUtf\fR when it is known to possibly contain upper ASCII characters whose possible combinations @@ -125,9 +127,9 @@ might be a UTF-8 special code. The string is parsed and executed directly (using \fBTcl_EvalObjv\fR) instead of compiling it and executing the bytecodes. In situations where it is known that the script will never be executed again, \fBTcl_Eval\fR may be faster than \fBTcl_EvalObjEx\fR. - \fBTcl_Eval\fR returns a completion code and result just like + \fBTcl_Eval\fR returns a completion code and result just like \fBTcl_EvalObjEx\fR. Note: for backward compatibility with versions before -Tcl 8.0, \fBTcl_Eval\fR copies the value result in \fIinterp\fR to +Tcl 8.0, \fBTcl_Eval\fR copies the object result in \fIinterp\fR to \fIinterp->result\fR (use is deprecated) where it can be accessed directly. This makes \fBTcl_Eval\fR somewhat slower than \fBTcl_EvalEx\fR, which does not do the copy. @@ -148,37 +150,33 @@ equivalent to using the \fBTCL_EVAL_GLOBAL\fR flag (see below). of any length, concatenates them into a single string, then calls \fBTcl_Eval\fR to execute that string as a Tcl command. It returns the result of the command and also modifies -the interpreter result in the same way as \fBTcl_Eval\fR. +\fIinterp->result\fR in the same way as \fBTcl_Eval\fR. The last argument to \fBTcl_VarEval\fR must be NULL to indicate the end -of arguments. +of arguments. \fBTcl_VarEval\fR is now deprecated. .PP \fBTcl_VarEvalVA\fR is the same as \fBTcl_VarEval\fR except that instead of taking a variable number of arguments it takes an argument -list. Interfaces using argument lists have been found to be nonportable -in practice. This function is deprecated and will be removed in Tcl 9.0. +list. Like \fBTcl_VarEval\fR, \fBTcl_VarEvalVA\fR is deprecated. .SH "FLAG BITS" -.PP -Any OR'ed combination of the following values may be used for the +Any ORed combination of the following values may be used for the \fIflags\fR argument to procedures such as \fBTcl_EvalObjEx\fR: .TP 23 \fBTCL_EVAL_DIRECT\fR -. This flag is only used by \fBTcl_EvalObjEx\fR; it is ignored by other procedures. If this flag bit is set, the script is not compiled to bytecodes; instead it is executed directly as is done by \fBTcl_EvalEx\fR. The \fBTCL_EVAL_DIRECT\fR flag is useful in situations where the -contents of a value are going to change immediately, so the +contents of an object are going to change immediately, so the bytecodes will not be reused in a future execution. In this case, it is faster to execute the script directly. .TP 23 \fBTCL_EVAL_GLOBAL\fR -. -If this flag is set, the script is evaluated in the global namespace instead of -the current namespace and its variable context consists of global variables -only (it ignores any Tcl procedures that are active). -.\" TODO: document TCL_EVAL_INVOKE and TCL_EVAL_NOERR. +If this flag is set, the script is processed at global level. This +means that it is evaluated in the global namespace and its variable +context consists of global variables only (it ignores any Tcl +procedures at are active). .SH "MISCELLANEOUS DETAILS" .PP @@ -204,21 +202,7 @@ and sets \fIinterp\fR's result to an error message indicating that the \fBreturn\fR, \fBbreak\fR, or \fBcontinue\fR command was invoked in an inappropriate place. This means that top-level applications should never see a return code -from \fBTcl_EvalObjEx\fR other than \fBTCL_OK\fR or \fBTCL_ERROR\fR. -.SH "REFERENCE COUNT MANAGEMENT" -.PP -\fBTcl_EvalObjEx\fR and \fBTcl_GlobalEvalObj\fR both increment and -decrement the reference count of their \fIobjPtr\fR argument; you must -not pass them any value with a reference count of zero. They also -manipulate the interpreter result; you must not count on the -interpreter result to hold the reference count of any value over -these calls. -.PP -\fBTcl_EvalObjv\fR may increment and decrement the reference count of -any value passed via its \fIobjv\fR argument; you must not pass any -value with a reference count of zero. This function also manipulates -the interpreter result; you must not count on the interpreter result -to hold the reference count of any value over this call. +from \fBTcl_EvalObjEx\fR other then \fBTCL_OK\fR or \fBTCL_ERROR\fR. .SH KEYWORDS -execute, file, global, result, script, value +execute, file, global, object, result, script |