Template:Ifdef/doc

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{{ifdef/doc}} is a compact variant of {{Qif}} for simple "if defined then do" statements without else part. It's the opposite of {{ifndef}}.

Contents 1 Usage 2 Example 3 Usage 4 Example 5 Caveats 6 See also 7 Usage 8 Example 9 Caveats 10 See also 11 Usage 12 Example 13 Caveats 14 See also 15 Usage 16 Example 17 Caveats 18 See also 19 Usage 20 Example 21 Caveats 22 See also 23 Usage 24 Example 25 Caveats 26 See also 27 Usage 28 Example 29 Caveats 30 See also 31 Usage 32 Example 33 Caveats 34 See also 35 Caveats 36 See also

[edit] Usage

{{Ifdef/doc|value|result}} yields result  if value  isn't blank.

This template is used to simplify the following equivalent but somewhat cryptic code variants:

{{{1{{{1|}}}|{{{2}}}}}}

{{{value{{{value|}}}|{{{result}}}}}}

{{{test{{{test|}}}|{{{then}}}}}}

[edit] Example

Code	Result
1 {{Ifdef/doc| |empty}}	1 {{ifdef/doc}} is a compact variant of {{Qif}} for simple "if defined then do" statements without else part. It's the opposite of {{ifndef}}. [edit] Usage {{Ifdef/doc|value|result}} yields result  if value  isn't blank. This template is used to simplify the following equivalent but somewhat cryptic code variants: {{{1{{{1|}}}|{{{2}}}}}} {{{value{{{value|}}}|{{{result}}}}}} {{{test{{{test|}}}|{{{then}}}}}} [edit] Example Code Result 1 {{Ifdef/doc| |empty}} 1 Template loop detected: Template:Ifdef/doc 2 {{Ifdef/doc|x|gotcha}} 2 Template loop detected: Template:Ifdef/doc 3 {{Ifdef/doc| {{{1| }}} | {{{1| }}} undefined}} 3 Template loop detected: Template:Ifdef/doc 4 {{Ifdef/doc| {{{1|x}}} | {{{1|x}}} for an u}} 4 Template loop detected: Template:Ifdef/doc 5 {{Ifdef/doc| {{{ 1 }}} | {{{1}}} bad idea}} 5 Template loop detected: Template:Ifdef/doc 6 {{Ifdef/doc| {{!}} |see also {{Tlx|Qif}} }} 6 Template loop detected: Template:Ifdef/doc 7 {{Ifdef/doc| okay | 2=see=[[#Caveats]] }} 7 Template loop detected: Template:Ifdef/doc 8 {{Ifdef/doc| oops | see=[[#Caveats]] }} 8 Template loop detected: Template:Ifdef/doc See also a simpler example using ifdef. There's no default in ifdef for the second parameter, because this could hide problematic code. [edit] Caveats In templates the characters "=" (=) and "|" (|) cannot be used as is in parameters. The numeric character references = and | are often good enough, but for Wiki and XHTML markup the literal characters are required: For | template:! (edit•talk•links•history) offers a workaround. For = the template parameter mechanism allows {{ifdef|1|2=ok=yes}} resulting in "ok=yes " instead of {{ifdef|1|bad=idea}} resulting in "{{{2}}} ". Substitution works only for {{ifdef}}, but not for {{ifndef}} or {{qif}}. [edit] See also template:Ifdef ( talk edit history links ) template:Ifndef ( talk edit history links ) template:Qif ( talk edit history links ) template:Tlx ( talk edit history links ) Parser functions #expr:, #if:, #ifeq:, etc.
2 {{Ifdef/doc|x|gotcha}}	2 {{ifdef/doc}} is a compact variant of {{Qif}} for simple "if defined then do" statements without else part. It's the opposite of {{ifndef}}. [edit] Usage {{Ifdef/doc|value|result}} yields result  if value  isn't blank. This template is used to simplify the following equivalent but somewhat cryptic code variants: {{{1{{{1|}}}|{{{2}}}}}} {{{value{{{value|}}}|{{{result}}}}}} {{{test{{{test|}}}|{{{then}}}}}} [edit] Example Code Result 1 {{Ifdef/doc| |empty}} 1 Template loop detected: Template:Ifdef/doc 2 {{Ifdef/doc|x|gotcha}} 2 Template loop detected: Template:Ifdef/doc 3 {{Ifdef/doc| {{{1| }}} | {{{1| }}} undefined}} 3 Template loop detected: Template:Ifdef/doc 4 {{Ifdef/doc| {{{1|x}}} | {{{1|x}}} for an u}} 4 Template loop detected: Template:Ifdef/doc 5 {{Ifdef/doc| {{{ 1 }}} | {{{1}}} bad idea}} 5 Template loop detected: Template:Ifdef/doc 6 {{Ifdef/doc| {{!}} |see also {{Tlx|Qif}} }} 6 Template loop detected: Template:Ifdef/doc 7 {{Ifdef/doc| okay | 2=see=[[#Caveats]] }} 7 Template loop detected: Template:Ifdef/doc 8 {{Ifdef/doc| oops | see=[[#Caveats]] }} 8 Template loop detected: Template:Ifdef/doc See also a simpler example using ifdef. There's no default in ifdef for the second parameter, because this could hide problematic code. [edit] Caveats In templates the characters "=" (=) and "|" (|) cannot be used as is in parameters. The numeric character references = and | are often good enough, but for Wiki and XHTML markup the literal characters are required: For | template:! (edit•talk•links•history) offers a workaround. For = the template parameter mechanism allows {{ifdef|1|2=ok=yes}} resulting in "ok=yes " instead of {{ifdef|1|bad=idea}} resulting in "{{{2}}} ". Substitution works only for {{ifdef}}, but not for {{ifndef}} or {{qif}}. [edit] See also template:Ifdef ( talk edit history links ) template:Ifndef ( talk edit history links ) template:Qif ( talk edit history links ) template:Tlx ( talk edit history links ) Parser functions #expr:, #if:, #ifeq:, etc.
3 {{Ifdef/doc| {{{1| }}} | {{{1| }}} undefined}}	3 {{ifdef/doc}} is a compact variant of {{Qif}} for simple "if defined then do" statements without else part. It's the opposite of {{ifndef}}. [edit] Usage {{Ifdef/doc|value|result}} yields result  if value  isn't blank. This template is used to simplify the following equivalent but somewhat cryptic code variants: {{{1{{{1|}}}|{{{2}}}}}} {{{value{{{value|}}}|{{{result}}}}}} {{{test{{{test|}}}|{{{then}}}}}} [edit] Example Code Result 1 {{Ifdef/doc| |empty}} 1 Template loop detected: Template:Ifdef/doc 2 {{Ifdef/doc|x|gotcha}} 2 Template loop detected: Template:Ifdef/doc 3 {{Ifdef/doc| {{{1| }}} | {{{1| }}} undefined}} 3 Template loop detected: Template:Ifdef/doc 4 {{Ifdef/doc| {{{1|x}}} | {{{1|x}}} for an u}} 4 Template loop detected: Template:Ifdef/doc 5 {{Ifdef/doc| {{{ 1 }}} | {{{1}}} bad idea}} 5 Template loop detected: Template:Ifdef/doc 6 {{Ifdef/doc| {{!}} |see also {{Tlx|Qif}} }} 6 Template loop detected: Template:Ifdef/doc 7 {{Ifdef/doc| okay | 2=see=[[#Caveats]] }} 7 Template loop detected: Template:Ifdef/doc 8 {{Ifdef/doc| oops | see=[[#Caveats]] }} 8 Template loop detected: Template:Ifdef/doc See also a simpler example using ifdef. There's no default in ifdef for the second parameter, because this could hide problematic code. [edit] Caveats In templates the characters "=" (=) and "|" (|) cannot be used as is in parameters. The numeric character references = and | are often good enough, but for Wiki and XHTML markup the literal characters are required: For | template:! (edit•talk•links•history) offers a workaround. For = the template parameter mechanism allows {{ifdef|1|2=ok=yes}} resulting in "ok=yes " instead of {{ifdef|1|bad=idea}} resulting in "{{{2}}} ". Substitution works only for {{ifdef}}, but not for {{ifndef}} or {{qif}}. [edit] See also template:Ifdef ( talk edit history links ) template:Ifndef ( talk edit history links ) template:Qif ( talk edit history links ) template:Tlx ( talk edit history links ) Parser functions #expr:, #if:, #ifeq:, etc.
4 {{Ifdef/doc| {{{1|x}}} | {{{1|x}}} for an u}}	4 {{ifdef/doc}} is a compact variant of {{Qif}} for simple "if defined then do" statements without else part. It's the opposite of {{ifndef}}. [edit] Usage {{Ifdef/doc|value|result}} yields result  if value  isn't blank. This template is used to simplify the following equivalent but somewhat cryptic code variants: {{{1{{{1|}}}|{{{2}}}}}} {{{value{{{value|}}}|{{{result}}}}}} {{{test{{{test|}}}|{{{then}}}}}} [edit] Example Code Result 1 {{Ifdef/doc| |empty}} 1 Template loop detected: Template:Ifdef/doc 2 {{Ifdef/doc|x|gotcha}} 2 Template loop detected: Template:Ifdef/doc 3 {{Ifdef/doc| {{{1| }}} | {{{1| }}} undefined}} 3 Template loop detected: Template:Ifdef/doc 4 {{Ifdef/doc| {{{1|x}}} | {{{1|x}}} for an u}} 4 Template loop detected: Template:Ifdef/doc 5 {{Ifdef/doc| {{{ 1 }}} | {{{1}}} bad idea}} 5 Template loop detected: Template:Ifdef/doc 6 {{Ifdef/doc| {{!}} |see also {{Tlx|Qif}} }} 6 Template loop detected: Template:Ifdef/doc 7 {{Ifdef/doc| okay | 2=see=[[#Caveats]] }} 7 Template loop detected: Template:Ifdef/doc 8 {{Ifdef/doc| oops | see=[[#Caveats]] }} 8 Template loop detected: Template:Ifdef/doc See also a simpler example using ifdef. There's no default in ifdef for the second parameter, because this could hide problematic code. [edit] Caveats In templates the characters "=" (=) and "|" (|) cannot be used as is in parameters. The numeric character references = and | are often good enough, but for Wiki and XHTML markup the literal characters are required: For | template:! (edit•talk•links•history) offers a workaround. For = the template parameter mechanism allows {{ifdef|1|2=ok=yes}} resulting in "ok=yes " instead of {{ifdef|1|bad=idea}} resulting in "{{{2}}} ". Substitution works only for {{ifdef}}, but not for {{ifndef}} or {{qif}}. [edit] See also template:Ifdef ( talk edit history links ) template:Ifndef ( talk edit history links ) template:Qif ( talk edit history links ) template:Tlx ( talk edit history links ) Parser functions #expr:, #if:, #ifeq:, etc.
5 {{Ifdef/doc| {{{ 1 }}} | {{{1}}} bad idea}}	5 {{ifdef/doc}} is a compact variant of {{Qif}} for simple "if defined then do" statements without else part. It's the opposite of {{ifndef}}. [edit] Usage {{Ifdef/doc|value|result}} yields result  if value  isn't blank. This template is used to simplify the following equivalent but somewhat cryptic code variants: {{{1{{{1|}}}|{{{2}}}}}} {{{value{{{value|}}}|{{{result}}}}}} {{{test{{{test|}}}|{{{then}}}}}} [edit] Example Code Result 1 {{Ifdef/doc| |empty}} 1 Template loop detected: Template:Ifdef/doc 2 {{Ifdef/doc|x|gotcha}} 2 Template loop detected: Template:Ifdef/doc 3 {{Ifdef/doc| {{{1| }}} | {{{1| }}} undefined}} 3 Template loop detected: Template:Ifdef/doc 4 {{Ifdef/doc| {{{1|x}}} | {{{1|x}}} for an u}} 4 Template loop detected: Template:Ifdef/doc 5 {{Ifdef/doc| {{{ 1 }}} | {{{1}}} bad idea}} 5 Template loop detected: Template:Ifdef/doc 6 {{Ifdef/doc| {{!}} |see also {{Tlx|Qif}} }} 6 Template loop detected: Template:Ifdef/doc 7 {{Ifdef/doc| okay | 2=see=[[#Caveats]] }} 7 Template loop detected: Template:Ifdef/doc 8 {{Ifdef/doc| oops | see=[[#Caveats]] }} 8 Template loop detected: Template:Ifdef/doc See also a simpler example using ifdef. There's no default in ifdef for the second parameter, because this could hide problematic code. [edit] Caveats In templates the characters "=" (=) and "|" (|) cannot be used as is in parameters. The numeric character references = and | are often good enough, but for Wiki and XHTML markup the literal characters are required: For | template:! (edit•talk•links•history) offers a workaround. For = the template parameter mechanism allows {{ifdef|1|2=ok=yes}} resulting in "ok=yes " instead of {{ifdef|1|bad=idea}} resulting in "{{{2}}} ". Substitution works only for {{ifdef}}, but not for {{ifndef}} or {{qif}}. [edit] See also template:Ifdef ( talk edit history links ) template:Ifndef ( talk edit history links ) template:Qif ( talk edit history links ) template:Tlx ( talk edit history links ) Parser functions #expr:, #if:, #ifeq:, etc.
6 {{Ifdef/doc| {{!}} |see also {{Tlx|Qif}} }}	6 {{ifdef/doc}} is a compact variant of {{Qif}} for simple "if defined then do" statements without else part. It's the opposite of {{ifndef}}. [edit] Usage {{Ifdef/doc|value|result}} yields result  if value  isn't blank. This template is used to simplify the following equivalent but somewhat cryptic code variants: {{{1{{{1|}}}|{{{2}}}}}} {{{value{{{value|}}}|{{{result}}}}}} {{{test{{{test|}}}|{{{then}}}}}} [edit] Example Code Result 1 {{Ifdef/doc| |empty}} 1 Template loop detected: Template:Ifdef/doc 2 {{Ifdef/doc|x|gotcha}} 2 Template loop detected: Template:Ifdef/doc 3 {{Ifdef/doc| {{{1| }}} | {{{1| }}} undefined}} 3 Template loop detected: Template:Ifdef/doc 4 {{Ifdef/doc| {{{1|x}}} | {{{1|x}}} for an u}} 4 Template loop detected: Template:Ifdef/doc 5 {{Ifdef/doc| {{{ 1 }}} | {{{1}}} bad idea}} 5 Template loop detected: Template:Ifdef/doc 6 {{Ifdef/doc| {{!}} |see also {{Tlx|Qif}} }} 6 Template loop detected: Template:Ifdef/doc 7 {{Ifdef/doc| okay | 2=see=[[#Caveats]] }} 7 Template loop detected: Template:Ifdef/doc 8 {{Ifdef/doc| oops | see=[[#Caveats]] }} 8 Template loop detected: Template:Ifdef/doc See also a simpler example using ifdef. There's no default in ifdef for the second parameter, because this could hide problematic code. [edit] Caveats In templates the characters "=" (=) and "|" (|) cannot be used as is in parameters. The numeric character references = and | are often good enough, but for Wiki and XHTML markup the literal characters are required: For | template:! (edit•talk•links•history) offers a workaround. For = the template parameter mechanism allows {{ifdef|1|2=ok=yes}} resulting in "ok=yes " instead of {{ifdef|1|bad=idea}} resulting in "{{{2}}} ". Substitution works only for {{ifdef}}, but not for {{ifndef}} or {{qif}}. [edit] See also template:Ifdef ( talk edit history links ) template:Ifndef ( talk edit history links ) template:Qif ( talk edit history links ) template:Tlx ( talk edit history links ) Parser functions #expr:, #if:, #ifeq:, etc.
7 {{Ifdef/doc| okay | 2=see=[[#Caveats]] }}	7 {{ifdef/doc}} is a compact variant of {{Qif}} for simple "if defined then do" statements without else part. It's the opposite of {{ifndef}}. [edit] Usage {{Ifdef/doc|value|result}} yields result  if value  isn't blank. This template is used to simplify the following equivalent but somewhat cryptic code variants: {{{1{{{1|}}}|{{{2}}}}}} {{{value{{{value|}}}|{{{result}}}}}} {{{test{{{test|}}}|{{{then}}}}}} [edit] Example Code Result 1 {{Ifdef/doc| |empty}} 1 Template loop detected: Template:Ifdef/doc 2 {{Ifdef/doc|x|gotcha}} 2 Template loop detected: Template:Ifdef/doc 3 {{Ifdef/doc| {{{1| }}} | {{{1| }}} undefined}} 3 Template loop detected: Template:Ifdef/doc 4 {{Ifdef/doc| {{{1|x}}} | {{{1|x}}} for an u}} 4 Template loop detected: Template:Ifdef/doc 5 {{Ifdef/doc| {{{ 1 }}} | {{{1}}} bad idea}} 5 Template loop detected: Template:Ifdef/doc 6 {{Ifdef/doc| {{!}} |see also {{Tlx|Qif}} }} 6 Template loop detected: Template:Ifdef/doc 7 {{Ifdef/doc| okay | 2=see=[[#Caveats]] }} 7 Template loop detected: Template:Ifdef/doc 8 {{Ifdef/doc| oops | see=[[#Caveats]] }} 8 Template loop detected: Template:Ifdef/doc See also a simpler example using ifdef. There's no default in ifdef for the second parameter, because this could hide problematic code. [edit] Caveats In templates the characters "=" (=) and "|" (|) cannot be used as is in parameters. The numeric character references = and | are often good enough, but for Wiki and XHTML markup the literal characters are required: For | template:! (edit•talk•links•history) offers a workaround. For = the template parameter mechanism allows {{ifdef|1|2=ok=yes}} resulting in "ok=yes " instead of {{ifdef|1|bad=idea}} resulting in "{{{2}}} ". Substitution works only for {{ifdef}}, but not for {{ifndef}} or {{qif}}. [edit] See also template:Ifdef ( talk edit history links ) template:Ifndef ( talk edit history links ) template:Qif ( talk edit history links ) template:Tlx ( talk edit history links ) Parser functions #expr:, #if:, #ifeq:, etc.
8 {{Ifdef/doc| oops | see=[[#Caveats]] }}	8 {{ifdef/doc}} is a compact variant of {{Qif}} for simple "if defined then do" statements without else part. It's the opposite of {{ifndef}}. [edit] Usage {{Ifdef/doc|value|result}} yields result  if value  isn't blank. This template is used to simplify the following equivalent but somewhat cryptic code variants: {{{1{{{1|}}}|{{{2}}}}}} {{{value{{{value|}}}|{{{result}}}}}} {{{test{{{test|}}}|{{{then}}}}}} [edit] Example Code Result 1 {{Ifdef/doc| |empty}} 1 Template loop detected: Template:Ifdef/doc 2 {{Ifdef/doc|x|gotcha}} 2 Template loop detected: Template:Ifdef/doc 3 {{Ifdef/doc| {{{1| }}} | {{{1| }}} undefined}} 3 Template loop detected: Template:Ifdef/doc 4 {{Ifdef/doc| {{{1|x}}} | {{{1|x}}} for an u}} 4 Template loop detected: Template:Ifdef/doc 5 {{Ifdef/doc| {{{ 1 }}} | {{{1}}} bad idea}} 5 Template loop detected: Template:Ifdef/doc 6 {{Ifdef/doc| {{!}} |see also {{Tlx|Qif}} }} 6 Template loop detected: Template:Ifdef/doc 7 {{Ifdef/doc| okay | 2=see=[[#Caveats]] }} 7 Template loop detected: Template:Ifdef/doc 8 {{Ifdef/doc| oops | see=[[#Caveats]] }} 8 Template loop detected: Template:Ifdef/doc See also a simpler example using ifdef. There's no default in ifdef for the second parameter, because this could hide problematic code. [edit] Caveats In templates the characters "=" (=) and "|" (|) cannot be used as is in parameters. The numeric character references = and | are often good enough, but for Wiki and XHTML markup the literal characters are required: For | template:! (edit•talk•links•history) offers a workaround. For = the template parameter mechanism allows {{ifdef|1|2=ok=yes}} resulting in "ok=yes " instead of {{ifdef|1|bad=idea}} resulting in "{{{2}}} ". Substitution works only for {{ifdef}}, but not for {{ifndef}} or {{qif}}. [edit] See also template:Ifdef ( talk edit history links ) template:Ifndef ( talk edit history links ) template:Qif ( talk edit history links ) template:Tlx ( talk edit history links ) Parser functions #expr:, #if:, #ifeq:, etc.

See also a simpler example using ifdef. There's no default in ifdef for the second parameter, because this could hide problematic code.

[edit] Caveats

In templates the characters "=" (=) and "|" (|) cannot be used as is in parameters. The numeric character references = and | are often good enough, but for Wiki and XHTML markup the literal characters are required:

1. For | template:! (edit•talk•links•history) offers a workaround.
2. For = the template parameter mechanism allows {{ifdef|1|2=ok=yes}} resulting in "ok=yes

" instead of {{ifdef|1|bad=idea}} resulting in "{{{2}}} ".

Substitution works only for {{ifdef}}, but not for {{ifndef}} or {{qif}}.

[edit] See also

• template:Ifdef ( talk edit history links )
• template:Ifndef ( talk edit history links )
• template:Qif ( talk edit history links )
• template:Tlx ( talk edit history links )
• Parser functions #expr:, #if:, #ifeq:, etc.