Mixing
Detect empty or null output from xstring's StrBetween
I have some code for formatting names. However, the ifempty macro from xifthen is unable to detect empty/null output from xstring macros such as StrBetween. The same goes for the equal {} method. How can I detect empty output from StrBetween? The below code for some reason compiles and does not work.
documentclass{article}
usepackage{xstring}
usepackage{xifthen}
newcommand{name}{John Doe}
newcommand{middleinitial}{%
StrBetween{name}{ }{.}
}
newcommand{test}{%
ifthenelse{isempty{middleinitial}}%
{Whoo hoo!}%
{Not whoo hoo.}
}
begin{document}
test
end{document}
Any ideas?
xstring xifthen
asked Jan 13 at 4:37
Adam EricksonAdam Erickson
1918
add a comment |
I have some code for formatting names. However, the ifempty macro from xifthen is unable to detect empty/null output from xstring macros such as StrBetween. The same goes for the equal {} method. How can I detect empty output from StrBetween? The below code for some reason compiles and does not work.
documentclass{article}
usepackage{xstring}
usepackage{xifthen}
newcommand{name}{John Doe}
newcommand{middleinitial}{%
StrBetween{name}{ }{.}
}
newcommand{test}{%
ifthenelse{isempty{middleinitial}}%
{Whoo hoo!}%
{Not whoo hoo.}
}
begin{document}
test
end{document}
Any ideas?
xstring xifthen
asked Jan 13 at 4:37
Adam EricksonAdam Erickson
1918
@Werner I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45
@ChristianHupfer I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45
add a comment |
I have some code for formatting names. However, the ifempty macro from xifthen is unable to detect empty/null output from xstring macros such as StrBetween. The same goes for the equal {} method. How can I detect empty output from StrBetween? The below code for some reason compiles and does not work.
documentclass{article}
usepackage{xstring}
usepackage{xifthen}
newcommand{name}{John Doe}
newcommand{middleinitial}{%
StrBetween{name}{ }{.}
}
newcommand{test}{%
ifthenelse{isempty{middleinitial}}%
{Whoo hoo!}%
{Not whoo hoo.}
}
begin{document}
test
end{document}
Any ideas?
xstring xifthen
asked Jan 13 at 4:37
Adam EricksonAdam Erickson
1918
I have some code for formatting names. However, the ifempty macro from xifthen is unable to detect empty/null output from xstring macros such as StrBetween. The same goes for the equal {} method. How can I detect empty output from StrBetween? The below code for some reason compiles and does not work.
documentclass{article}
usepackage{xstring}
usepackage{xifthen}
newcommand{name}{John Doe}
newcommand{middleinitial}{%
StrBetween{name}{ }{.}
}
newcommand{test}{%
ifthenelse{isempty{middleinitial}}%
{Whoo hoo!}%
{Not whoo hoo.}
}
begin{document}
test
end{document}
Any ideas?
xstring xifthen
xstring xifthen
asked Jan 13 at 4:37
Adam EricksonAdam Erickson
1918
asked Jan 13 at 4:37
Adam EricksonAdam Erickson
1918
edited Jan 13 at 6:26
Adam Erickson
asked Jan 13 at 4:37
Adam EricksonAdam Erickson
1918
asked Jan 13 at 4:37
Adam EricksonAdam Erickson
1918
asked Jan 13 at 4:37
Adam EricksonAdam Erickson
1918
1918
@Werner I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45
@ChristianHupfer I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45
add a comment |
@Werner I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45
@ChristianHupfer I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45
@Werner I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45
@Werner I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45
@ChristianHupfer I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45
@ChristianHupfer I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45
add a comment |
3 Answers
3
active
oldest
votes
middleinitial is not expandable, and therefore you cannot properly test whether there is a middle initial in name or not. You'll have to store the output (the middle initial) first using the optional argument at the end of StrBetween{<str>}{<from>}{<to>}[<macro>] and then you can check for an empty argument:
documentclass{article}
usepackage{xstring}
newcommand{name}{John Doe}
makeatletter
newcommand{middleinitial}{%
StrBetween{name}{ }{.}[@middleinitial]%
}
newcommand{test}{%
middleinitial% Find middle initial
% https://tex.stackexchange.com/q/53068/5764
ifrelaxdetokenizeexpandafter{@middleinitial}relax
Whoo hoo!% No middle initial
else
Not whoo hoo.% A middle initial
fi
}
makeatother
begin{document}
test % Whoo hoo.
renewcommand{name}{John F. Doe}%
test % Not whoo hoo!
end{document}
answered Jan 13 at 5:12
WernerWerner
443k689791678
What is this monstrosity:expandafterifexpandafterrelaxexpandafterdetokenizeexpandafter{@middleinitial}relax?
– Adam Erickson
Jan 13 at 6:25
Also, thank you for your fast solution : ) Isn't it possible to doStrBetween{name}{ }{.}[middleinitial]without thenewcommandstatement?
– Adam Erickson
Jan 14 at 16:26
@AdamErickson: The monstrosity can be made shorter (updated in the answer). It's required to expand@middleinitialbefore it being processed bydetokenize, hence theexpandafter.
– Werner
Jan 14 at 16:30
@AdamErickson: You mean is it necessary to have anewcommand{middleinitial}? It's not necessary. You can includeStrBetween{name}{ }{.}[@middleinitial]as part oftest.
– Werner
Jan 14 at 16:31
Thank you, that is much cleaner and easier to comprehend!
– Adam Erickson
Jan 14 at 16:40
|
show 11 more comments
Werner already explained, why middleinitial isn't expandable due to the usage of xstring macros.
I present a shorter way in order to test for the emptiness of middleinitial by using ifblank from etoolbox package. There are still two expandafter statements required, but not a bunch of 5 of them. In addition, I find etoolbox much more convenient than ifthen or xifthen.
expandafterifblankexpandafter{middleinitial}{true branch}{false branch} is necessary, because ifblank does not expand its first argument, i.e. without expandafter the macro 'sees' middleinitial, but not what the content which is stored in that macro. It must be expanded first before ifblank performs the test.
The expandafter primitive looks ahead of ifblank, i.e. it ignores ifblank first and detects the { of the first argument. Unfortunately, this is not what is desired (and not expandable anyway), so we must jump over { again, i.e.
expandafterifblankexpandafter{middleinitial}{...}{...}
will allow TeX/LaTeX to 'jump' over ifblank to the second expandafter, that jumps over { to middleinitial and expands that sequence -- after this is done, TeX continues with ifblank{expanded version of middleinitial}{...}{...} and performs the test finally.
documentclass{article}
usepackage{xstring}
usepackage{etoolbox}
newcommand{name}{John C. Doe}
newcommand{othername}{John Doe}
newcommand{testinitial}[3]{%
begingroup
StrBetween{#1}{ }{.}[middleinitial]%
expandafterifblankexpandafter{middleinitial}{#2}{#3}%
endgroup
}
begin{document}
testinitial{name}{Whoo hoo!}{Not whoo hoo.}
testinitial{othername}{Whoo hoo!}{Not whoo hoo.}
end{document}
answered Jan 13 at 7:25
Christian HupferChristian Hupfer
150k15199394
1
Thank you for your solution.
– Adam Erickson
Jan 14 at 16:27
@AdamErickson: You're welcome
– Christian Hupfer
Jan 14 at 16:31
add a comment |
Thank you, @Werner and @ChristianHupfer! Based on your solutions, I've found another solution using xstring that appears quite clean:
documentclass{article}
usepackage{xstring}
newcommand{name}{John Doe}
makeatletter
newcommand{middleinitial}{%
StrBetween{name}{ }{.}[@middleinitial]%
}
newcommand{test}{%
middleinitial % Find middle initial
IfStrEq{@middleinitial}{}%
{Whoo hoo!}%
{Not whoo hoo.}%
}
makeatother
begin{document}
test % Whoo hoo.
renewcommand{name}{John F. Doe}%
test % Not whoo hoo!
end{document}
I've posted a follow-up question with a more vexing expansion problem related to IfStrEqual and IfSubStr here (link) if anyone can help.
answered Jan 17 at 17:40
Adam EricksonAdam Erickson
1918
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
middleinitial is not expandable, and therefore you cannot properly test whether there is a middle initial in name or not. You'll have to store the output (the middle initial) first using the optional argument at the end of StrBetween{<str>}{<from>}{<to>}[<macro>] and then you can check for an empty argument:
documentclass{article}
usepackage{xstring}
newcommand{name}{John Doe}
makeatletter
newcommand{middleinitial}{%
StrBetween{name}{ }{.}[@middleinitial]%
}
newcommand{test}{%
middleinitial% Find middle initial
% https://tex.stackexchange.com/q/53068/5764
ifrelaxdetokenizeexpandafter{@middleinitial}relax
Whoo hoo!% No middle initial
else
Not whoo hoo.% A middle initial
fi
}
makeatother
begin{document}
test % Whoo hoo.
renewcommand{name}{John F. Doe}%
test % Not whoo hoo!
end{document}
answered Jan 13 at 5:12
WernerWerner
443k689791678
What is this monstrosity:expandafterifexpandafterrelaxexpandafterdetokenizeexpandafter{@middleinitial}relax?
– Adam Erickson
Jan 13 at 6:25
Also, thank you for your fast solution : ) Isn't it possible to doStrBetween{name}{ }{.}[middleinitial]without thenewcommandstatement?
– Adam Erickson
Jan 14 at 16:26
@AdamErickson: The monstrosity can be made shorter (updated in the answer). It's required to expand@middleinitialbefore it being processed bydetokenize, hence theexpandafter.
– Werner
Jan 14 at 16:30
@AdamErickson: You mean is it necessary to have anewcommand{middleinitial}? It's not necessary. You can includeStrBetween{name}{ }{.}[@middleinitial]as part oftest.
– Werner
Jan 14 at 16:31
Thank you, that is much cleaner and easier to comprehend!
– Adam Erickson
Jan 14 at 16:40
|
show 11 more comments
middleinitial is not expandable, and therefore you cannot properly test whether there is a middle initial in name or not. You'll have to store the output (the middle initial) first using the optional argument at the end of StrBetween{<str>}{<from>}{<to>}[<macro>] and then you can check for an empty argument:
documentclass{article}
usepackage{xstring}
newcommand{name}{John Doe}
makeatletter
newcommand{middleinitial}{%
StrBetween{name}{ }{.}[@middleinitial]%
}
newcommand{test}{%
middleinitial% Find middle initial
% https://tex.stackexchange.com/q/53068/5764
ifrelaxdetokenizeexpandafter{@middleinitial}relax
Whoo hoo!% No middle initial
else
Not whoo hoo.% A middle initial
fi
}
makeatother
begin{document}
test % Whoo hoo.
renewcommand{name}{John F. Doe}%
test % Not whoo hoo!
end{document}
answered Jan 13 at 5:12
WernerWerner
443k689791678
What is this monstrosity:expandafterifexpandafterrelaxexpandafterdetokenizeexpandafter{@middleinitial}relax?
– Adam Erickson
Jan 13 at 6:25
Also, thank you for your fast solution : ) Isn't it possible to doStrBetween{name}{ }{.}[middleinitial]without thenewcommandstatement?
– Adam Erickson
Jan 14 at 16:26
@AdamErickson: The monstrosity can be made shorter (updated in the answer). It's required to expand@middleinitialbefore it being processed bydetokenize, hence theexpandafter.
– Werner
Jan 14 at 16:30
@AdamErickson: You mean is it necessary to have anewcommand{middleinitial}? It's not necessary. You can includeStrBetween{name}{ }{.}[@middleinitial]as part oftest.
– Werner
Jan 14 at 16:31
Thank you, that is much cleaner and easier to comprehend!
– Adam Erickson
Jan 14 at 16:40
|
show 11 more comments
middleinitial is not expandable, and therefore you cannot properly test whether there is a middle initial in name or not. You'll have to store the output (the middle initial) first using the optional argument at the end of StrBetween{<str>}{<from>}{<to>}[<macro>] and then you can check for an empty argument:
documentclass{article}
usepackage{xstring}
newcommand{name}{John Doe}
makeatletter
newcommand{middleinitial}{%
StrBetween{name}{ }{.}[@middleinitial]%
}
newcommand{test}{%
middleinitial% Find middle initial
% https://tex.stackexchange.com/q/53068/5764
ifrelaxdetokenizeexpandafter{@middleinitial}relax
Whoo hoo!% No middle initial
else
Not whoo hoo.% A middle initial
fi
}
makeatother
begin{document}
test % Whoo hoo.
renewcommand{name}{John F. Doe}%
test % Not whoo hoo!
end{document}
answered Jan 13 at 5:12
WernerWerner
443k689791678
middleinitial is not expandable, and therefore you cannot properly test whether there is a middle initial in name or not. You'll have to store the output (the middle initial) first using the optional argument at the end of StrBetween{<str>}{<from>}{<to>}[<macro>] and then you can check for an empty argument:
documentclass{article}
usepackage{xstring}
newcommand{name}{John Doe}
makeatletter
newcommand{middleinitial}{%
StrBetween{name}{ }{.}[@middleinitial]%
}
newcommand{test}{%
middleinitial% Find middle initial
% https://tex.stackexchange.com/q/53068/5764
ifrelaxdetokenizeexpandafter{@middleinitial}relax
Whoo hoo!% No middle initial
else
Not whoo hoo.% A middle initial
fi
}
makeatother
begin{document}
test % Whoo hoo.
renewcommand{name}{John F. Doe}%
test % Not whoo hoo!
end{document}
answered Jan 13 at 5:12
WernerWerner
443k689791678
edited Jan 14 at 16:29
answered Jan 13 at 5:12
WernerWerner
443k689791678
answered Jan 13 at 5:12
WernerWerner
443k689791678
answered Jan 13 at 5:12
WernerWerner
443k689791678
443k689791678
What is this monstrosity:expandafterifexpandafterrelaxexpandafterdetokenizeexpandafter{@middleinitial}relax?
– Adam Erickson
Jan 13 at 6:25
Also, thank you for your fast solution : ) Isn't it possible to doStrBetween{name}{ }{.}[middleinitial]without thenewcommandstatement?
– Adam Erickson
Jan 14 at 16:26
@AdamErickson: The monstrosity can be made shorter (updated in the answer). It's required to expand@middleinitialbefore it being processed bydetokenize, hence theexpandafter.
– Werner
Jan 14 at 16:30
@AdamErickson: You mean is it necessary to have anewcommand{middleinitial}? It's not necessary. You can includeStrBetween{name}{ }{.}[@middleinitial]as part oftest.
– Werner
Jan 14 at 16:31
Thank you, that is much cleaner and easier to comprehend!
– Adam Erickson
Jan 14 at 16:40
|
show 11 more comments
What is this monstrosity:expandafterifexpandafterrelaxexpandafterdetokenizeexpandafter{@middleinitial}relax?
– Adam Erickson
Jan 13 at 6:25
Also, thank you for your fast solution : ) Isn't it possible to doStrBetween{name}{ }{.}[middleinitial]without thenewcommandstatement?
– Adam Erickson
Jan 14 at 16:26
@AdamErickson: The monstrosity can be made shorter (updated in the answer). It's required to expand@middleinitialbefore it being processed bydetokenize, hence theexpandafter.
– Werner
Jan 14 at 16:30
@AdamErickson: You mean is it necessary to have anewcommand{middleinitial}? It's not necessary. You can includeStrBetween{name}{ }{.}[@middleinitial]as part oftest.
– Werner
Jan 14 at 16:31
Thank you, that is much cleaner and easier to comprehend!
– Adam Erickson
Jan 14 at 16:40
What is this monstrosity:
expandafterifexpandafterrelaxexpandafterdetokenizeexpandafter{@middleinitial}relax?– Adam Erickson
Jan 13 at 6:25
What is this monstrosity:
expandafterifexpandafterrelaxexpandafterdetokenizeexpandafter{@middleinitial}relax?– Adam Erickson
Jan 13 at 6:25
Also, thank you for your fast solution : ) Isn't it possible to do
StrBetween{name}{ }{.}[middleinitial] without the newcommand statement?– Adam Erickson
Jan 14 at 16:26
Also, thank you for your fast solution : ) Isn't it possible to do
StrBetween{name}{ }{.}[middleinitial] without the newcommand statement?– Adam Erickson
Jan 14 at 16:26
@AdamErickson: The monstrosity can be made shorter (updated in the answer). It's required to expand
@middleinitial before it being processed by detokenize, hence the expandafter.– Werner
Jan 14 at 16:30
@AdamErickson: The monstrosity can be made shorter (updated in the answer). It's required to expand
@middleinitial before it being processed by detokenize, hence the expandafter.– Werner
Jan 14 at 16:30
@AdamErickson: You mean is it necessary to have a
newcommand{middleinitial}? It's not necessary. You can include StrBetween{name}{ }{.}[@middleinitial] as part of test.– Werner
Jan 14 at 16:31
@AdamErickson: You mean is it necessary to have a
newcommand{middleinitial}? It's not necessary. You can include StrBetween{name}{ }{.}[@middleinitial] as part of test.– Werner
Jan 14 at 16:31
Thank you, that is much cleaner and easier to comprehend!
– Adam Erickson
Jan 14 at 16:40
Thank you, that is much cleaner and easier to comprehend!
– Adam Erickson
Jan 14 at 16:40
|
show 11 more comments
Werner already explained, why middleinitial isn't expandable due to the usage of xstring macros.
I present a shorter way in order to test for the emptiness of middleinitial by using ifblank from etoolbox package. There are still two expandafter statements required, but not a bunch of 5 of them. In addition, I find etoolbox much more convenient than ifthen or xifthen.
expandafterifblankexpandafter{middleinitial}{true branch}{false branch} is necessary, because ifblank does not expand its first argument, i.e. without expandafter the macro 'sees' middleinitial, but not what the content which is stored in that macro. It must be expanded first before ifblank performs the test.
The expandafter primitive looks ahead of ifblank, i.e. it ignores ifblank first and detects the { of the first argument. Unfortunately, this is not what is desired (and not expandable anyway), so we must jump over { again, i.e.
expandafterifblankexpandafter{middleinitial}{...}{...}
will allow TeX/LaTeX to 'jump' over ifblank to the second expandafter, that jumps over { to middleinitial and expands that sequence -- after this is done, TeX continues with ifblank{expanded version of middleinitial}{...}{...} and performs the test finally.
documentclass{article}
usepackage{xstring}
usepackage{etoolbox}
newcommand{name}{John C. Doe}
newcommand{othername}{John Doe}
newcommand{testinitial}[3]{%
begingroup
StrBetween{#1}{ }{.}[middleinitial]%
expandafterifblankexpandafter{middleinitial}{#2}{#3}%
endgroup
}
begin{document}
testinitial{name}{Whoo hoo!}{Not whoo hoo.}
testinitial{othername}{Whoo hoo!}{Not whoo hoo.}
end{document}
answered Jan 13 at 7:25
Christian HupferChristian Hupfer
150k15199394
1
Thank you for your solution.
– Adam Erickson
Jan 14 at 16:27
@AdamErickson: You're welcome
– Christian Hupfer
Jan 14 at 16:31
add a comment |
Werner already explained, why middleinitial isn't expandable due to the usage of xstring macros.
I present a shorter way in order to test for the emptiness of middleinitial by using ifblank from etoolbox package. There are still two expandafter statements required, but not a bunch of 5 of them. In addition, I find etoolbox much more convenient than ifthen or xifthen.
expandafterifblankexpandafter{middleinitial}{true branch}{false branch} is necessary, because ifblank does not expand its first argument, i.e. without expandafter the macro 'sees' middleinitial, but not what the content which is stored in that macro. It must be expanded first before ifblank performs the test.
The expandafter primitive looks ahead of ifblank, i.e. it ignores ifblank first and detects the { of the first argument. Unfortunately, this is not what is desired (and not expandable anyway), so we must jump over { again, i.e.
expandafterifblankexpandafter{middleinitial}{...}{...}
will allow TeX/LaTeX to 'jump' over ifblank to the second expandafter, that jumps over { to middleinitial and expands that sequence -- after this is done, TeX continues with ifblank{expanded version of middleinitial}{...}{...} and performs the test finally.
documentclass{article}
usepackage{xstring}
usepackage{etoolbox}
newcommand{name}{John C. Doe}
newcommand{othername}{John Doe}
newcommand{testinitial}[3]{%
begingroup
StrBetween{#1}{ }{.}[middleinitial]%
expandafterifblankexpandafter{middleinitial}{#2}{#3}%
endgroup
}
begin{document}
testinitial{name}{Whoo hoo!}{Not whoo hoo.}
testinitial{othername}{Whoo hoo!}{Not whoo hoo.}
end{document}
answered Jan 13 at 7:25
Christian HupferChristian Hupfer
150k15199394
1
Thank you for your solution.
– Adam Erickson
Jan 14 at 16:27
@AdamErickson: You're welcome
– Christian Hupfer
Jan 14 at 16:31
add a comment |
Werner already explained, why middleinitial isn't expandable due to the usage of xstring macros.
I present a shorter way in order to test for the emptiness of middleinitial by using ifblank from etoolbox package. There are still two expandafter statements required, but not a bunch of 5 of them. In addition, I find etoolbox much more convenient than ifthen or xifthen.
expandafterifblankexpandafter{middleinitial}{true branch}{false branch} is necessary, because ifblank does not expand its first argument, i.e. without expandafter the macro 'sees' middleinitial, but not what the content which is stored in that macro. It must be expanded first before ifblank performs the test.
The expandafter primitive looks ahead of ifblank, i.e. it ignores ifblank first and detects the { of the first argument. Unfortunately, this is not what is desired (and not expandable anyway), so we must jump over { again, i.e.
expandafterifblankexpandafter{middleinitial}{...}{...}
will allow TeX/LaTeX to 'jump' over ifblank to the second expandafter, that jumps over { to middleinitial and expands that sequence -- after this is done, TeX continues with ifblank{expanded version of middleinitial}{...}{...} and performs the test finally.
documentclass{article}
usepackage{xstring}
usepackage{etoolbox}
newcommand{name}{John C. Doe}
newcommand{othername}{John Doe}
newcommand{testinitial}[3]{%
begingroup
StrBetween{#1}{ }{.}[middleinitial]%
expandafterifblankexpandafter{middleinitial}{#2}{#3}%
endgroup
}
begin{document}
testinitial{name}{Whoo hoo!}{Not whoo hoo.}
testinitial{othername}{Whoo hoo!}{Not whoo hoo.}
end{document}
answered Jan 13 at 7:25
Christian HupferChristian Hupfer
150k15199394
Werner already explained, why middleinitial isn't expandable due to the usage of xstring macros.
I present a shorter way in order to test for the emptiness of middleinitial by using ifblank from etoolbox package. There are still two expandafter statements required, but not a bunch of 5 of them. In addition, I find etoolbox much more convenient than ifthen or xifthen.
expandafterifblankexpandafter{middleinitial}{true branch}{false branch} is necessary, because ifblank does not expand its first argument, i.e. without expandafter the macro 'sees' middleinitial, but not what the content which is stored in that macro. It must be expanded first before ifblank performs the test.
The expandafter primitive looks ahead of ifblank, i.e. it ignores ifblank first and detects the { of the first argument. Unfortunately, this is not what is desired (and not expandable anyway), so we must jump over { again, i.e.
expandafterifblankexpandafter{middleinitial}{...}{...}
will allow TeX/LaTeX to 'jump' over ifblank to the second expandafter, that jumps over { to middleinitial and expands that sequence -- after this is done, TeX continues with ifblank{expanded version of middleinitial}{...}{...} and performs the test finally.
documentclass{article}
usepackage{xstring}
usepackage{etoolbox}
newcommand{name}{John C. Doe}
newcommand{othername}{John Doe}
newcommand{testinitial}[3]{%
begingroup
StrBetween{#1}{ }{.}[middleinitial]%
expandafterifblankexpandafter{middleinitial}{#2}{#3}%
endgroup
}
begin{document}
testinitial{name}{Whoo hoo!}{Not whoo hoo.}
testinitial{othername}{Whoo hoo!}{Not whoo hoo.}
end{document}
answered Jan 13 at 7:25
Christian HupferChristian Hupfer
150k15199394
edited Jan 13 at 7:43
answered Jan 13 at 7:25
Christian HupferChristian Hupfer
150k15199394
answered Jan 13 at 7:25
Christian HupferChristian Hupfer
150k15199394
answered Jan 13 at 7:25
Christian HupferChristian Hupfer
150k15199394
150k15199394
1
Thank you for your solution.
– Adam Erickson
Jan 14 at 16:27
@AdamErickson: You're welcome
– Christian Hupfer
Jan 14 at 16:31
add a comment |
1
Thank you for your solution.
– Adam Erickson
Jan 14 at 16:27
@AdamErickson: You're welcome
– Christian Hupfer
Jan 14 at 16:31
1
1
Thank you for your solution.
– Adam Erickson
Jan 14 at 16:27
Thank you for your solution.
– Adam Erickson
Jan 14 at 16:27
@AdamErickson: You're welcome
– Christian Hupfer
Jan 14 at 16:31
@AdamErickson: You're welcome
– Christian Hupfer
Jan 14 at 16:31
add a comment |
Thank you, @Werner and @ChristianHupfer! Based on your solutions, I've found another solution using xstring that appears quite clean:
documentclass{article}
usepackage{xstring}
newcommand{name}{John Doe}
makeatletter
newcommand{middleinitial}{%
StrBetween{name}{ }{.}[@middleinitial]%
}
newcommand{test}{%
middleinitial % Find middle initial
IfStrEq{@middleinitial}{}%
{Whoo hoo!}%
{Not whoo hoo.}%
}
makeatother
begin{document}
test % Whoo hoo.
renewcommand{name}{John F. Doe}%
test % Not whoo hoo!
end{document}
I've posted a follow-up question with a more vexing expansion problem related to IfStrEqual and IfSubStr here (link) if anyone can help.
answered Jan 17 at 17:40
Adam EricksonAdam Erickson
1918
add a comment |
Thank you, @Werner and @ChristianHupfer! Based on your solutions, I've found another solution using xstring that appears quite clean:
documentclass{article}
usepackage{xstring}
newcommand{name}{John Doe}
makeatletter
newcommand{middleinitial}{%
StrBetween{name}{ }{.}[@middleinitial]%
}
newcommand{test}{%
middleinitial % Find middle initial
IfStrEq{@middleinitial}{}%
{Whoo hoo!}%
{Not whoo hoo.}%
}
makeatother
begin{document}
test % Whoo hoo.
renewcommand{name}{John F. Doe}%
test % Not whoo hoo!
end{document}
I've posted a follow-up question with a more vexing expansion problem related to IfStrEqual and IfSubStr here (link) if anyone can help.
answered Jan 17 at 17:40
Adam EricksonAdam Erickson
1918
add a comment |
Thank you, @Werner and @ChristianHupfer! Based on your solutions, I've found another solution using xstring that appears quite clean:
documentclass{article}
usepackage{xstring}
newcommand{name}{John Doe}
makeatletter
newcommand{middleinitial}{%
StrBetween{name}{ }{.}[@middleinitial]%
}
newcommand{test}{%
middleinitial % Find middle initial
IfStrEq{@middleinitial}{}%
{Whoo hoo!}%
{Not whoo hoo.}%
}
makeatother
begin{document}
test % Whoo hoo.
renewcommand{name}{John F. Doe}%
test % Not whoo hoo!
end{document}
I've posted a follow-up question with a more vexing expansion problem related to IfStrEqual and IfSubStr here (link) if anyone can help.
answered Jan 17 at 17:40
Adam EricksonAdam Erickson
1918
Thank you, @Werner and @ChristianHupfer! Based on your solutions, I've found another solution using xstring that appears quite clean:
documentclass{article}
usepackage{xstring}
newcommand{name}{John Doe}
makeatletter
newcommand{middleinitial}{%
StrBetween{name}{ }{.}[@middleinitial]%
}
newcommand{test}{%
middleinitial % Find middle initial
IfStrEq{@middleinitial}{}%
{Whoo hoo!}%
{Not whoo hoo.}%
}
makeatother
begin{document}
test % Whoo hoo.
renewcommand{name}{John F. Doe}%
test % Not whoo hoo!
end{document}
I've posted a follow-up question with a more vexing expansion problem related to IfStrEqual and IfSubStr here (link) if anyone can help.
answered Jan 17 at 17:40
Adam EricksonAdam Erickson
1918
edited Jan 17 at 22:31
answered Jan 17 at 17:40
Adam EricksonAdam Erickson
1918
answered Jan 17 at 17:40
Adam EricksonAdam Erickson
1918
answered Jan 17 at 17:40
Adam EricksonAdam Erickson
1918
1918
add a comment |
add a comment |
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@Werner I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45
@ChristianHupfer I've opened a new question here: tex.stackexchange.com/questions/470467/…
– Adam Erickson
Jan 17 at 0:45