Stop Jinja2 Execution With IF Statement?

up vote
0
down vote

favorite

I have some code like:

{% if key_var is not none %}

  {{ my_list[key_var] }}

{% endif %}

However, I'm getting an error:

jinja2.exceptions.UndefinedError: 'list object' has no attribute 'None'

Is there a way to get Jinja2 to not run the code if the IF statement is false? Or am I missing something else?

Thank you for your help :)

edited Nov 8 at 18:17

asked Nov 8 at 17:47

VFR292

1314

Why not {% if key_var %} and leave it at that?
– dfundako
Nov 8 at 18:20

That snippet works for me on the latest Jinja2 (2.10). What version of Jinja2 are you using? And are you sure that that fragment is the culprit?
– Dave W. Smith
Nov 8 at 18:35

@dfundako Because zero would do the wrong thing
– Dave W. Smith
Nov 8 at 18:38

I'm using Jinja2 2.9.6. I'll see if I can upgrade to 2.10.
– VFR292
Nov 9 at 3:32

add a comment |

up vote
0
down vote

favorite

I have some code like:

{% if key_var is not none %}

  {{ my_list[key_var] }}

{% endif %}

However, I'm getting an error:

jinja2.exceptions.UndefinedError: 'list object' has no attribute 'None'

Is there a way to get Jinja2 to not run the code if the IF statement is false? Or am I missing something else?

Thank you for your help :)

edited Nov 8 at 18:17

asked Nov 8 at 17:47

VFR292

1314

Why not {% if key_var %} and leave it at that?
– dfundako
Nov 8 at 18:20

That snippet works for me on the latest Jinja2 (2.10). What version of Jinja2 are you using? And are you sure that that fragment is the culprit?
– Dave W. Smith
Nov 8 at 18:35

@dfundako Because zero would do the wrong thing
– Dave W. Smith
Nov 8 at 18:38

I'm using Jinja2 2.9.6. I'll see if I can upgrade to 2.10.
– VFR292
Nov 9 at 3:32

add a comment |

up vote
0
down vote

favorite

I have some code like:

{% if key_var is not none %}

  {{ my_list[key_var] }}

{% endif %}

However, I'm getting an error:

jinja2.exceptions.UndefinedError: 'list object' has no attribute 'None'

Is there a way to get Jinja2 to not run the code if the IF statement is false? Or am I missing something else?

Thank you for your help :)

edited Nov 8 at 18:17

asked Nov 8 at 17:47

VFR292

1314

I have some code like:

{% if key_var is not none %}

  {{ my_list[key_var] }}

{% endif %}

However, I'm getting an error:

jinja2.exceptions.UndefinedError: 'list object' has no attribute 'None'

Is there a way to get Jinja2 to not run the code if the IF statement is false? Or am I missing something else?

Thank you for your help :)

django flask jinja2

edited Nov 8 at 18:17

asked Nov 8 at 17:47

VFR292

1314

edited Nov 8 at 18:17

asked Nov 8 at 17:47

VFR292

1314

edited Nov 8 at 18:17

asked Nov 8 at 17:47

VFR292

1314

asked Nov 8 at 17:47

VFR292

1314

asked Nov 8 at 17:47

VFR292

1314

Why not {% if key_var %} and leave it at that?
– dfundako
Nov 8 at 18:20

That snippet works for me on the latest Jinja2 (2.10). What version of Jinja2 are you using? And are you sure that that fragment is the culprit?
– Dave W. Smith
Nov 8 at 18:35

@dfundako Because zero would do the wrong thing
– Dave W. Smith
Nov 8 at 18:38

I'm using Jinja2 2.9.6. I'll see if I can upgrade to 2.10.
– VFR292
Nov 9 at 3:32

add a comment |

Why not {% if key_var %} and leave it at that?
– dfundako
Nov 8 at 18:20

That snippet works for me on the latest Jinja2 (2.10). What version of Jinja2 are you using? And are you sure that that fragment is the culprit?
– Dave W. Smith
Nov 8 at 18:35

@dfundako Because zero would do the wrong thing
– Dave W. Smith
Nov 8 at 18:38

I'm using Jinja2 2.9.6. I'll see if I can upgrade to 2.10.
– VFR292
Nov 9 at 3:32

Why not {% if key_var %} and leave it at that?
– dfundako
Nov 8 at 18:20

That snippet works for me on the latest Jinja2 (2.10). What version of Jinja2 are you using? And are you sure that that fragment is the culprit?
– Dave W. Smith
Nov 8 at 18:35

@dfundako Because zero would do the wrong thing
– Dave W. Smith
Nov 8 at 18:38

I'm using Jinja2 2.9.6. I'll see if I can upgrade to 2.10.
– VFR292
Nov 9 at 3:32

add a comment |

1 Answer
1

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votes

up vote
0
down vote

{% if my_list[key_var] is defined %}

  {{ my_list[key_var] }}

{% endif %}

Got the behavior I was looking for. I didn't want my_list[key_var] to run inside of the IF statement when the key_var is None

I don't know why this worked when my original attempt didn't. If anyone knows, please fill me in.

Thank you!

answered Nov 9 at 4:06

VFR292

1314

add a comment |

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1 Answer
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active

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1 Answer
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active

oldest

votes

up vote
0
down vote

{% if my_list[key_var] is defined %}

  {{ my_list[key_var] }}

{% endif %}

Got the behavior I was looking for. I didn't want my_list[key_var] to run inside of the IF statement when the key_var is None

I don't know why this worked when my original attempt didn't. If anyone knows, please fill me in.

Thank you!

answered Nov 9 at 4:06

VFR292

1314

add a comment |

up vote
0
down vote

{% if my_list[key_var] is defined %}

  {{ my_list[key_var] }}

{% endif %}

Got the behavior I was looking for. I didn't want my_list[key_var] to run inside of the IF statement when the key_var is None

I don't know why this worked when my original attempt didn't. If anyone knows, please fill me in.

Thank you!

answered Nov 9 at 4:06

VFR292

1314

add a comment |

up vote
0
down vote

{% if my_list[key_var] is defined %}

  {{ my_list[key_var] }}

{% endif %}

Got the behavior I was looking for. I didn't want my_list[key_var] to run inside of the IF statement when the key_var is None

I don't know why this worked when my original attempt didn't. If anyone knows, please fill me in.

Thank you!

answered Nov 9 at 4:06

VFR292

1314

{% if my_list[key_var] is defined %}

  {{ my_list[key_var] }}

{% endif %}

Got the behavior I was looking for. I didn't want my_list[key_var] to run inside of the IF statement when the key_var is None

I don't know why this worked when my original attempt didn't. If anyone knows, please fill me in.

Thank you!

answered Nov 9 at 4:06

VFR292

1314

answered Nov 9 at 4:06

VFR292

1314

answered Nov 9 at 4:06

VFR292

1314

answered Nov 9 at 4:06

VFR292

1314

add a comment |

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