TrueQ¶

Status: Stable

documented, exercised by the test suite and/or worked examples, with no known limitations recorded.

Description¶

TrueQ[expr] yields True if expr is True, and False otherwise.

Examples (3)¶

Every input below was run against the current Mathilda build and its output recorded.

Applications (3)¶

In[1]:= TrueQ[True]
Out[1]= True

In[2]:= TrueQ[x]
Out[2]= False

In[3]:= TrueQ[1 < 2]
Out[3]= True

Implementation notes¶

builtin_trueq is a one-argument predicate (no Hold attributes, so its argument is already evaluated). It returns the symbol True only when the argument is exactly the interned symbol True (pointer equality on SYM_True), and False for everything else — so unlike a bare condition it never stays symbolic. A non-unary call returns NULL.

Attributes: Protected.

References¶

Source: src/cond.c
Specification: docs/spec/builtins/control-flow.md
Tests: tests/test_boolean.c
Tests: tests/test_cond.c
Tests: tests/test_mateigen_direct.c
Tests: tests/test_risch_residue_split.c

Notes & additional examples¶

Notes¶

TrueQ yields True only when its argument evaluates to the symbol True; anything else (including unevaluated symbolic expressions) yields False, making it useful as a safe guard in conditions.