Basic Examples (2) 

Take all elements until an odd number is encountered:

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Use a pure function to take all elements until the first element above 10:

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Scope (4) 

Elements of the list can be any expression:

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Use TakeUntil to take elements from a list until the first element that satisfies the given test is found:

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By default, TakeUntil returns the entire list when no element satisfies the condition:

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TakeUntil returns the entire list when the element that satisfies the test is the last one in the list:

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Generalizations & Extensions (1) 

Use TakeUntil on an expression with head f:

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Applications (1) 

Find the digits of GoldenRatio up to and including the first occurrence of a 7:

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Properties & Relations (5) 

When the test for TakeUntil is the logical negation of the test for TakeWhile, the result of TakeWhile is always contained within the result of TakeUntil. For example:

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If the test function always returns False, TakeUntil will return the entire list. For example:

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When using TakeUntil with an Association, it operates on the Values:

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Use TakeUntil with the resource function SymbolQ:

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Use TakeUntil with the resource function PossibleNameQ:

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Possible Issues (1) 

If the criterion does not return strictly boolean values (True or False), TakeUntil will treat any non-True value as False. For example:

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Neat Examples (1) 

Use TakeUntil on a list of integer pairs, with a condition to stop at the first pair where the total exceeds a specified threshold:

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