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Content :typeset [ {+|-}AHUaghlmrtux ] [ {+|-}EFLRZip [ n ] ] [ + ] [ name[=value] ... ] typeset -T [ {+|-}Uglrux ] [ {+|-}LRZp [ n ] ] [ + | SCALAR[=value] array[=(value ...)] [ sep ] ] typeset -f [ {+|-}TUkmtuz ] [ + ] [ name ... ] Set or display attributes and values for shell parameters. Except as noted below for control flags that change the behav- ior, a parameter is created for each name that does not already refer to one. When inside a function, a new parameter is cre- ated for every name (even those that already exist), and is un- set again when the function completes. See `Local Parameters' in zshparam(1). The same rules apply to special shell parame- ters, which retain their special attributes when made local. For each name=value assignment, the parameter name is set to value. If the shell option TYPESET_SILENT is not set, for each remain- ing name that refers to a parameter that is already set, the name and value of the parameter are printed in the form of an assignment. Nothing is printed for newly-created parameters, or when any attribute flags listed below are given along with the name. Using `+' instead of minus to introduce an attribute turns it off. If no name is present, the names and values of all parameters are printed. In this case the attribute flags restrict the dis- play to only those parameters that have the specified at- tributes, and using `+' rather than `-' to introduce the flag suppresses printing of the values of parameters when there is no parameter name. All forms of the command handle scalar assignment. Array as- signment is possible if any of the reserved words declare, ex- port, float, integer, local, readonly or typeset is matched when the line is parsed (N.B. not when it is executed). In this case the arguments are parsed as assignments, except that the `+=' syntax and the GLOB_ASSIGN option are not supported, and scalar values after = are not split further into words, even if ex- panded (regardless of the setting of the KSH_TYPESET option; this option is obsolete). Examples of the differences between command and reserved word parsing: # Reserved word parsing typeset svar=$(echo one word) avar=(several words) The above creates a scalar parameter svar and an array parameter avar as if the assignments had been svar="one word" avar=(several words) On the other hand: # Normal builtin interface builtin typeset svar=$(echo two words) The builtin keyword causes the above to use the standard builtin interface to typeset in which argument parsing is performed in the same way as for other commands. This example creates a scalar svar containing the value two and another scalar parame- ter words with no value. An array value in this case would ei- ther cause an error or be treated as an obscure set of glob qualifiers. Arbitrary arguments are allowed if they take the form of assign- ments after command line expansion; however, these only perform scalar assignment: var='svar=val' typeset $var The above sets the scalar parameter svar to the value val. Parentheses around the value within var would not cause array assignment as they will be treated as ordinary characters when $var is substituted. Any non-trivial expansion in the name part of the assignment causes the argument to be treated in this fashion: typeset {var1,var2,var3}=name The above syntax is valid, and has the expected effect of set- ting the three parameters to the same value, but the command line is parsed as a set of three normal command line arguments to typeset after expansion. Hence it is not possible to assign to multiple arrays by this means. Note that each interface to any of the commands my be disabled separately. For example, `disable -r typeset' disables the re- served word interface to typeset, exposing the builtin inter- face, while `disable typeset' disables the builtin. Note that disabling the reserved word interface for typeset may cause problems with the output of `typeset -p', which assumes the re- served word interface is available in order to restore array and associative array values. Unlike parameter assignment statements, typeset's exit status on an assignment that involves a command substitution does not re- flect the exit status of the command substitution. Therefore, to test for an error in a command substitution, separate the declaration of the parameter from its initialization: # WRONG typeset var1=$(exit 1) || echo "Trouble with var1" # RIGHT typeset var1 && var1=$(exit 1) || echo "Trouble with var1" To initialize a parameter param to a command output and mark it readonly, use typeset -r param or readonly param after the pa- rameter assignment statement. If no attribute flags are given, and either no name arguments are present or the flag +m is used, then each parameter name printed is preceded by a list of the attributes of that parame- ter (array, association, exported, float, integer, readonly, or undefined for autoloaded parameters not yet loaded). If +m is used with attribute flags, and all those flags are introduced with +, the matching parameter names are printed but their val- ues are not. The following control flags change the behavior of typeset: + If `+' appears by itself in a separate word as the last option, then the names of all parameters (functions with -f) are printed, but the values (function bodies) are not. No name arguments may appear, and it is an error for any other options to follow `+'. The effect of `+' is as if all attribute flags which precede it were given with a `+' prefix. For example, `typeset -U +' is equiv- alent to `typeset +U' and displays the names of all ar- rays having the uniqueness attribute, whereas `typeset -f -U +' displays the names of all autoloadable functions. If + is the only option, then type information (array, readonly, etc.) is also printed for each parameter, in the same manner as `typeset +m "*"'. -g The -g (global) means that any resulting parameter will not be restricted to local scope. Note that this does not necessarily mean that the parameter will be global, as the flag will apply to any existing parameter (even if unset) from an enclosing function. This flag does not affect the parameter after creation, hence it has no ef- fect when listing existing parameters, nor does the flag +g have any effect except in combination with -m (see be- low). -m If the -m flag is given the name arguments are taken as patterns (use quoting to prevent these from being inter- preted as file patterns). With no attribute flags, all parameters (or functions with the -f flag) with matching names are printed (the shell option TYPESET_SILENT is not used in this case). If the +g flag is combined with -m, a new local parameter is created for every matching parameter that is not al- ready local. Otherwise -m applies all other flags or as- signments to the existing parameters. Except when assignments are made with name=value, using +m forces the matching parameters and their attributes to be printed, even inside a function. Note that -m is ig- nored if no patterns are given, so `typeset -m' displays attributes but `typeset -a +m' does not. -p [ n ] If the -p option is given, parameters and values are printed in the form of a typeset command with an assign- ment, regardless of other flags and options. Note that the -H flag on parameters is respected; no value will be shown for these parameters. -p may be followed by an optional integer argument. Cur- rently only the value 1 is supported. In this case ar- rays and associative arrays are printed with newlines be- tween indented elements for readability. -T [ scalar[=value] array[=(value ...)] [ sep ] ] This flag has a different meaning when used with -f; see below. Otherwise the -T option requires zero, two, or three arguments to be present. With no arguments, the list of parameters created in this fashion is shown. With two or three arguments, the first two are the name of a scalar and of an array parameter (in that order) that will be tied together in the manner of $PATH and $path. The optional third argument is a single-character separator which will be used to join the elements of the array to form the scalar; if absent, a colon is used, as with $PATH. Only the first character of the separator is significant; any remaining characters are ignored. Multibyte characters are not yet supported. Only one of the scalar and array parameters may be as- signed an initial value (the restrictions on assignment forms described above also apply). Both the scalar and the array may be manipulated as nor- mal. If one is unset, the other will automatically be unset too. There is no way of untying the variables without unsetting them, nor of converting the type of one of them with another typeset command; +T does not work, assigning an array to scalar is an error, and assigning a scalar to array sets it to be a single-element array. Note that both `typeset -xT ...' and `export -T ...' work, but only the scalar will be marked for export. Setting the value using the scalar version causes a split on all separators (which cannot be quoted). It is possi- ble to apply -T to two previously tied variables but with a different separator character, in which case the vari- ables remain joined as before but the separator is changed. When an existing scalar is tied to a new array, the value of the scalar is preserved but no attribute other than export will be preserved. Attribute flags that transform the final value (-L, -R, -Z, -l, -u) are only applied to the expanded value at the point of a pa- rameter expansion expression using `$'. They are not applied when a parameter is retrieved internally by the shell for any purpose. The following attribute flags may be specified: -A The names refer to associative array parameters; see `Ar- ray Parameters' in zshparam(1). -L [ n ] Left justify and remove leading blanks from the value when the parameter is expanded. If n is nonzero, it de- fines the width of the field. If n is zero, the width is determined by the width of the value of the first assign- ment. In the case of numeric parameters, the length of the complete value assigned to the parameter is used to determine the width, not the value that would be output. The width is the count of characters, which may be multi- byte characters if the MULTIBYTE option is in effect. Note that the screen width of the character is not taken into account; if this is required, use padding with pa- rameter expansion flags ${(ml...)...} as described in `Parameter Expansion Flags' in zshexpn(1). When the parameter is expanded, it is filled on the right with blanks or truncated if necessary to fit the field. Note truncation can lead to unexpected results with nu- meric parameters. Leading zeros are removed if the -Z flag is also set. -R [ n ] Similar to -L, except that right justification is used; when the parameter is expanded, the field is left filled with blanks or truncated from the end. May not be com- bined with the -Z flag. -U For arrays (but not for associative arrays), keep only the first occurrence of each duplicated value. This may also be set for tied parameters (see -T) or colon-sepa- rated special parameters like PATH or FIGNORE, etc. Note the flag takes effect on assignment, and the type of the variable being assigned to is determinative; for vari- ables with shared values it is therefore recommended to set the flag for all interfaces, e.g. `typeset -U PATH path'. This flag has a different meaning when used with -f; see below. -Z [ n ] Specially handled if set along with the -L flag. Other- wise, similar to -R, except that leading zeros are used for padding instead of blanks if the first non-blank character is a digit. Numeric parameters are specially handled: they are always eligible for padding with ze- roes, and the zeroes are inserted at an appropriate place in the output. -a The names refer to array parameters. An array parameter may be created this way, but it may be assigned to in the typeset statement only if the reserved word form of type- set is enabled (as it is by default). When displaying, both normal and associative arrays are shown. -f The names refer to functions rather than parameters. No assignments can be made, and the only other valid flags are -t, -T, -k, -u, -U and -z. The flag -t turns on exe- cution tracing for this function; the flag -T does the same, but turns off tracing for any named (not anonymous) function called from the present one, unless that func- tion also has the -t or -T flag. The -u and -U flags cause the function to be marked for autoloading; -U also causes alias expansion to be suppressed when the function is loaded. See the description of the `autoload' builtin for details. Note that the builtin functions provides the same basic capabilities as typeset -f but gives access to a few ex- tra options; autoload gives further additional options for the case typeset -fu and typeset -fU. -h Hide: only useful for special parameters (those marked `<S>' in the table in zshparam(1)), and for local parame- ters with the same name as a special parameter, though harmless for others. A special parameter with this at- tribute will not retain its special effect when made lo- cal. Thus after `typeset -h PATH', a function containing `typeset PATH' will create an ordinary local parameter without the usual behaviour of PATH. Alternatively, the local parameter may itself be given this attribute; hence inside a function `typeset -h PATH' creates an ordinary local parameter and the special PATH parameter is not al- tered in any way. It is also possible to create a local parameter using `typeset +h special', where the local copy of special will retain its special properties re- gardless of having the -h attribute. Global special pa- rameters loaded from shell modules (currently those in zsh/mapfile and zsh/parameter) are automatically given the -h attribute to avoid name clashes. -H Hide value: specifies that typeset will not display the value of the parameter when listing parameters; the dis- play for such parameters is always as if the `+' flag had been given. Use of the parameter is in other respects normal, and the option does not apply if the parameter is specified by name, or by pattern with the -m option. This is on by default for the parameters in the zsh/pa- rameter and zsh/mapfile modules. Note, however, that un- like the -h flag this is also useful for non-special pa- rameters. -i [ n ] Use an internal integer representation. If n is nonzero it defines the output arithmetic base, otherwise it is determined by the first assignment. Bases from 2 to 36 inclusive are allowed. -E [ n ] Use an internal double-precision floating point represen- tation. On output the variable will be converted to sci- entific notation. If n is nonzero it defines the number of significant figures to display; the default is ten. -F [ n ] Use an internal double-precision floating point represen- tation. On output the variable will be converted to fixed-point decimal notation. If n is nonzero it defines the number of digits to display after the decimal point; the default is ten. -l Convert the result to lower case whenever the parameter is expanded. The value is not converted when assigned. -r The given names are marked readonly. Note that if name is a special parameter, the readonly attribute can be turned on, but cannot then be turned off. If the POSIX_BUILTINS option is set, the readonly attri- bute is more restrictive: unset variables can be marked readonly and cannot then be set; furthermore, the read- only attribute cannot be removed from any variable. It is still possible to change other attributes of the variable though, some of which like -U or -Z would affect the value. More generally, the readonly attribute should not be relied on as a security mechanism. Note that in zsh (like in pdksh but unlike most other shells) it is still possible to create a local variable of the same name as this is considered a different vari- able (though this variable, too, can be marked readonly). Special variables that have been made readonly retain their value and readonly attribute when made local. -t Tags the named parameters. Tags have no special meaning to the shell. This flag has a different meaning when used with -f; see above. -u Convert the result to upper case whenever the parameter is expanded. The value is not converted when assigned. This flag has a different meaning when used with -f; see above. -x Mark for automatic export to the environment of subse- quently executed commands. If the option GLOBAL_EXPORT is set, this implies the option -g, unless +g is also ex- plicitly given; in other words the parameter is not made local to the enclosing function. This is for compatibil- ity with previous versions of zsh. declare Same as typeset. float [ {+|-}Hghlprtux ] [ {+|-}EFLRZ [ n ] ] [ name[=value] ... ] Equivalent to typeset -E, except that options irrelevant to floating point numbers are not permitted. integer [ {+|-}Hghlprtux ] [ {+|-}LRZi [ n ] ] [ name[=value] ... ] Equivalent to typeset -i, except that options irrelevant to in- tegers are not permitted. local [ {+|-}AHUahlprtux ] [ {+|-}EFLRZi [ n ] ] [ name[=value] ... ] Same as typeset, except that the options -g, and -f are not per- mitted. In this case the -x option does not force the use of -g, i.e. exported variables will be local to functions. readonly Same as typeset -r. With the POSIX_BUILTINS option set, same as typeset -gr.

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