Sponsored Content
Top Forums Shell Programming and Scripting Use parameter expansion over a parameter expansion in bash. Post 303043430 by MadeInGermany on Tuesday 28th of January 2020 12:34:06 PM
Old 01-28-2020
Really interesting. By definition it is a variable modifier that means the LHS must be a variable. Nesting can only be attempted on the RHS that is a string.
Apparently in zsh the LHS can be a string that means it is a full functional operator.
This User Gave Thanks to MadeInGermany For This Post:
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

removing html tags via parameter expansion

Hi all- I have a variable that contains a web page: echo $STUFF <html> <head> <title>my page</title></head> <body> blah blah etc.. Can I use the shell's parameter expansion abilities to remove just the tags? I thought that FIXHTML=${STUFF//<*>/} might do it, but it didn't seem to... (2 Replies)
Discussion started by: rev66
2 Replies

2. Shell Programming and Scripting

Need to print the expansion of the found string (the expansion is beween two delimiters '-' , '||'

Hi , could anyone help me out with this problem. sample.txt has this content : u001- this is used for project1 || u002- this is used for p2|| not to be printed u003- this is used for project3 || u004- this is used for p4 || u005- this is used for project5 || u006- this is used for p6... (9 Replies)
Discussion started by: Balaji PK
9 Replies

3. Shell Programming and Scripting

Need help with parameter expansion

Say you have this numeric variable that can be set by the user but you never want it to leave a certain range when it gets printed. How could you use parameter expansion such that it will never expand outside of that boundary? Thanks ---------- Post updated at 11:09 PM ---------- Previous update... (3 Replies)
Discussion started by: stevenswj
3 Replies

4. Shell Programming and Scripting

Bash parameter expansion from a config file

Hi - I am trying to do a simple config file with known variable names in it, e.g.: contents of config file a.conf: -a -b $work -c $host simplified contents of bash script file: work='trunk' host='alaska' opts=$(tr '\n' ' ' < a.conf) opts="$opts $*" mycommand $opts arg1 arg2 The... (3 Replies)
Discussion started by: mrengert
3 Replies

5. Shell Programming and Scripting

Parameter expansion not working for all strings...

I'm trying to write a script that parses my music collection and hard link some filenames that my media player doesn't like to other names. To do this I need to extract the name and remove alla non ASCII characters from that and do a cp -l with the result. Problem is this: 22:16:58 $... (8 Replies)
Discussion started by: refuser
8 Replies

6. UNIX for Dummies Questions & Answers

Parameter Expansion with regular expression

Hello experts, I am exploring parameter expansion, and trying to cut the fields in a URL. Following is the requirement: I have // abc.nnt /dir1/dir2/dir3/dir4/somefile.java What i need to get is the path after dir3, and dir3 will be passed. output that i need is... (1 Reply)
Discussion started by: gjarms
1 Replies

7. Shell Programming and Scripting

Bash Parameter Expansion

I have made the following examples that print various parameter expansions text: iv-hhz-sac/hpac/hhz.d/iv.hpac..hhz.d.2016.250.070018.sac (text%.*): iv-hhz-sac/hpac/hhz.d/iv.hpac..hhz.d.2016.250.070018 (text%%.*): iv-hhz-sac/hpac/hhz (text#*.): d/iv.hpac..hhz.d.2016.250.070018.sac... (2 Replies)
Discussion started by: kristinu
2 Replies

8. Shell Programming and Scripting

Bash Parameter Expansion

#!/bin/bash SNMPW='/usr/bin/snmpwalk' while read h i do loc=$($SNMPW -v3 -u 'Myusername' -l authPriv -a SHA -A 'Password1' -x AES -X 'Password2' $i sysLocation.0 2>/dev/null) loc=${loc:-" is not snmpable."} loc=${loc##*: } loc=${loc//,/} echo "$i,$h,$loc" done < $1 My question is ... ... (1 Reply)
Discussion started by: sumguy
1 Replies

9. Shell Programming and Scripting

Bash : More parameter expansion and IFS

I am trying to become more fluent with the interworking of bash and minimize the number of external calls. Sample Data. This will be the response of the snmp query. SNMPv2-MIB::sysName.0 = STRING: SomeHostName SNMPv2-MIB::sysObjectID.0 = OID: SNMPv2-SMI::enterprises.9.1.1745... (5 Replies)
Discussion started by: sumguy
5 Replies

10. Shell Programming and Scripting

Bash : Parameter expansion ${var:-file*}

Example data $ ls *somehost* 10.10.10.10_somehost1.xyz.com.log 11.11.11.11_somehost2.xyz.com.log #!/bin/bash #FILES="*.log" FILES=${FILES:-*.log} for x in $FILES do ip="${x%%_*}" # isolate IP address x="${x##*_}" # isolate hostname hnam="${x%.*}" # Remove the ".log"... (2 Replies)
Discussion started by: popeye
2 Replies
FBB::TypeTrait(3bobcat) 					   Error handler					   FBB::TypeTrait(3bobcat)

NAME
FBB::TypeTrait - shortdesc SYNOPSIS
#include <bobcat/typetrait> DESCRIPTION
FBB::TypeTrait is a traits class. It does not define any member functions or data members, but merely types. It can be used to determine the basic type and other characteristics of (const) plain, (const) pointer or (const) reference types. It was designed after Alexandrescu's(2001) TypeTraits template class. The FBB::LpromotesR class template is used to determine, compile-time, whether its second (right-hand side) template type can be promoted to its first (left-hand side) template type. The FBB::Use class template expects two typenames LHS and RHS and defines typename Use<LHS, RHS>::type as LHS if RHS can be promoted to LHS or it defines typename Use<LHS, RHS>::type as RHS. NAMESPACE
FBB All constructors, members, operators and manipulators, mentioned in this man-page, are defined in the namespace FBB. INHERITS FROM
- TypeTrait<;TYPE> TYPE is the template type parameter whose characteristics must be determined. TypeTrait<TYPE> defines the type Plain: the plain type (the type without const, pointer, reference type indication) of any const or non-const plain, pointer, lvalue- or rvalue-reference type. TypeTrait<TYPE> defines the following bool values: o isClass: true if the template type argument represents a class (struct) type, false otherwise. o isConst: true if the template type argument represents a const type, false otherwise. o isPointer: true if the template type argument represents a pointer type, false otherwise. o isR_Ref: true if the template type argument represents a rvalue reference type, false otherwise. o isRef: true if the template type argument represents an lvalue reference type, false otherwise. LpromotesR<;LeftType, RightType> LpromotesR<LeftType, RightType> defines the enum constant yes as 1 if an RightType argument can be promoted to LeftType value or object. The enum value yes is defined as 0 if no such constructor is available or if such a constructor is defined using the explicit keyword. EXAMPLES
Here is an example using LpromotesR: int main() { cout << "string promotes char const *: " << LpromotesR<string, char const *>::yes << ' '; // 1 cout << "string promotes string " << LpromotesR<string, string>::yes << ' '; // 1 cout << "char const * promotes string " << LpromotesR<char const *, string>::yes << ' '; // 0 } FILES
bobcat/typetrait - defines the class interface SEE ALSO
bobcat(7) Alexandrescu A.(2001) Modern C++ Design, Addison-Wesley, Boston. BUGS
None Reported. DISTRIBUTION FILES
o bobcat_3.01.00-x.dsc: detached signature; o bobcat_3.01.00-x.tar.gz: source archive; o bobcat_3.01.00-x_i386.changes: change log; o libbobcat1_3.01.00-x_*.deb: debian package holding the libraries; o libbobcat1-dev_3.01.00-x_*.deb: debian package holding the libraries, headers and manual pages; o http://sourceforge.net/projects/bobcat: public archive location; BOBCAT
Bobcat is an acronym of `Brokken's Own Base Classes And Templates'. COPYRIGHT
This is free software, distributed under the terms of the GNU General Public License (GPL). AUTHOR
Frank B. Brokken (f.b.brokken@rug.nl). libbobcat1-dev_3.01.00-x.tar.gz 2005-2012 FBB::TypeTrait(3bobcat)
All times are GMT -4. The time now is 07:00 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy