Handlebars strict mode undefined variable behavior

Handlebars: Helper '{{unknownHelper}}' is not defined – strict‑mode variable rendering uncertainty

0 reputation · 05 Mar 2024, 05:12 UTC

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Goal: Determine whether Handlebars renders an undefined variable as an empty string or throws an error when strict mode is enabled, considering version differences and the compat flag.

Uncertainty: Reports indicate that Handlebars v4.x may output an empty string while v5.x may throw an Error, and the presence of the compat flag can alter this outcome, leaving the exact behavior undefined for developers relying on strict mode.

Does Handlebars v5.x with strict:true and compat:false throw an Error or render an empty string for a template containing {{missingVar}}?
How does enabling the compat flag change the behavior in both v4.x and v5.x?

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Handlebars: Helper '{{unknownHelper}}' is not defined – strict‑mode variable rendering uncertainty

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