It is to be noted that this action is not one for advice and instruction in connection with the settlement of an estate (Trust Co. v. Barrett, 238 N.C. 579, 78 S.E. 2d 730) ; nor is it an ordinary suit for the construction of specific items of a will (Cansler v. McLaughlin, 238 N.C. 197, 77 S.E. 2d 618). The plaintiffs in their complaint challenge the validity of the trust provisions of the will. They assert that these provisions are void in toto. The attack is general and broadside. They allege, without further elaboration, that the trust is void, for that its provisions are (1) uncertain, (2) repugnant, and (3) violate the rule against perpetuities. We discuss these grounds of attack seriatim.

1. The question of uncertainty. — When the validity of an item in a will is challenged on the ground of uncertainty, it will be declared void on that ground only when its terms are so indefinite and uncertain that the court, in applying the usual rules of construction, is unable to declare the intention of the testator for the reason that in legal contemplation there was no expression of intention on his part. 57 Am. Jur., Wills, Sec. 34. See also White v. University, 39 N.C. 19; McLeod v. Jones, 159 N.C. 74, 74 S.E. 733; Reid v. Neal, 182 N.C. 192, 108 S.E. 769.

No such uncertainty appears in connection with the trust provisions of this will. Under “Item II” of the will the residuary estate of the testator is devised and bequeathed to “Ingram P. Hedgpeth, as Trustee.” The trust so created is an active one (Fisher v. Fisher, 218 N.C. 42, 47, 9 S.E. 2d 493), under which the widow, Edna Britt, “during the term of her life or widowhood” is to receive the entire net income.

It seems to be conceded, and rightly so, that there is no uncertainty or vagueness as to the provisions made for the widow during her life or widowhood. This being so, the allegation that the trust is void for uncertainty may not be sustained. This is so for the reason that if the trust provisions are good in any respect, or to any extent, the plaintiffs’ broadside challenge must fail. Therefore for the purpose of decision we pursue the question of uncertainty no further.

*377 However, we note in passing certain questions raised in tbe plaintiffs’ brief respecting possible uncertainties as to wbo will take portions of tbe property in tbe event of tbe death of one or more of tbe testator’s cbildren without leaving cbildren. These are premature, speculative questions of interpretation to be determined if and when they arise in tbe future. They are not presented for review by this record. See Burchett v. Mason, 233 N.C. 306, 308, 63 S.E. 2d 634.

2. The question of repugnancy. — There is no merit in the plaintiffs’ contentions that the trust provisions are void for repugnancy. These contentions are too unsubstantial to require extended discussion. Illustrative of these contentions: Plaintiffs point to the provisions of Paragraph (f) of Item II of the will and Item 1 of the second codicil, both of which deal with the same property, with the codicil making a disposition of the property entirely different from the will. Here the plaintiffs make the contention that both provisions are void for repugnancy because the codicil does not in express language revoke the corresponding item of the will. As to this, it is enough to say that the provisions of the codicil revoke the corresponding provisions of the will by clear implication. It is elemental that “a codicil plainly inconsistent with the provisions of the will operates, to the extent of the inconsistency, as a revocation of the will even in the absence of any express words of revocation.” 57 Am. Jur., Wills, Sec. 485; Armstrong v. Armstrong, 235 N.C. 733, 735, 71 S.E. 2d 119. See also Jenkins v. Maxwell, 52 N.C. 612; Dalton v. Houston, 58 N.C. 401; Annotations, 51 A.L.R. 712; 123 Id. 1406.

3. The rule against perpetuities. — Tbe essential elements of this rule are stated succinctly by Barnhill, J., in McQueen v. Trust Co., 234 N.C. 737, 741, 68 S.E. 2d 831, as follows: “. . . no devise or grant of a future interest in property is valid unless title thereto must vest, if at all, not less than twenty-one years, plus tbe period of gestation, after some life or lives in being, at tbe time of tbe creation of the interest.” Dean Mordecai states tbe rule in abbreviated form this way: “Every estate must vest during a life or lives in being and twenty-one years — plus tbe usual period of gestation — thereafter.” Mordecai’s Law Lectures, Section Edition, p. 589.

Tbe controlling factor in the application of the rule against perpetuities is the time when a future interest vests, rather than the time when it comes into enjoyment. McQueen v. Trust Co., supra.

Here it is provided that on termination of the widow’s estate durante viduitate the fee simple title to specifically designated portions of the trust realty shall vest immediately in certain named cbildren and .grandchildren of the testator, with direction that the possession and use of designated parcels of the residue of the trust realty be set over to named cbildren and grandchildren of the testator living when the will was made, *378 for the period of their lives, with further direction that upon the death of these life beneficiaries the trust shall terminate and the various parcels of realty held by them shall be set over and conveyed in fee simple to the ultimate beneficiaries of the trust.

It is manifest that all interests created by the trust provisions of this will vest within the time allowed by the rule against perpetuities. McQueen v. Trust Co., supra, and cases there cited.

It follows from what we have said that the judgment below is

Affirmed.